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\n - \n \n \n
![\"About](\"path/to/image.jpg\" "\\"\\"")
\n\n\nSlideshow plugin\n\nIf you\u2019re not familiar with jQuery or how to write and author your own plugin there are plenty of articles to help you out.\n\njQuery has a chainable interface and this is something your plugin must implement. This is easy to achieve, so your plugin simply returns the collection it is using:\n\nreturn this.each(\n\tfunction () {}\n};\n\nLocal Variables\n\nTo keep the JavaScript clean and avoid any conflicts, you must set up any variables which are local to the plugin and should be used on each collection item. Defining all your variables at the top under one statement makes adding more and finding which variables are used easier. For other tips, conventions and improvements check out JSLint, the \u201cJavaScript Code Quality Tool\u201d.\n\nvar $$, $div, $images, $arrows, $pager,\n\tid, selector, path, o, options,\n\theight, width,\n\tlist = [], li = 0,\n\tparts = [], pi = 0,\n\tarrows = ['Previous', 'Next'];\n\nCache jQuery Objects\n\nIt is good practice to cache any calls made to jQuery. This reduces wasted DOM calls, can improve the speed of your JavaScript code and makes code more reusable.\n\nThe following code snippet caches the current selected DOM element as a jQuery object using the variable name $$. Secondly, the plugin makes its settings available to the Metadata plugin\u2021 which is best practice within jQuery plugins.\n\nFor each slideshow the plugin generates a with a class of slideshow and a unique id. This is used to wrap the slideshow images, pagination and controls.\n\nThe base path which is used for all the images in the slideshow is calculated based on the existing image which appears on the page. For example, if the path to the image on the page was /img/flowers/1.jpg the plugin would use the path /img/flowers/ to load the other images.\n\n$$ = $(this);\no = $.metadata ? $.extend({}, settings, $$.metadata()) : settings;\nid = 'slideshow-' + (i++ + 1);\n$div = $('').addClass('slideshow').attr('id', id);\nselector = '#' + id + ' ';\npath = $$.attr('src').replace(/[0-9]\\.jpg/g, '');\noptions = {};\nheight = $$.height();\nwidth = $$.width();\n\nNote: the plugin uses conventions such as folder structure and numeric filenames. These conventions help with the reusable aspect of plugins and best practices.\n\nBuild the Images\n\nThe cycle plugin uses a list of images to create the slideshow. Because we chose to start with one image we must now build the list programmatically. This is a case of looping through the images which were added via the plugin options, building the appropriate HTML and appending the resulting
- to the DOM.\n\n$.each(o.images, function () {\n\tlist[li++] = '
- ';\n\tlist[li++] = '
';\n\tlist[li++] = '
';\n});\n$images = $(' - ';\n\t\tparts[pi++] = '';\n\t\tparts[pi++] = '' + val + '';\n\t\tparts[pi++] = '';\n\t\tparts[pi++] = ' ';\n\t});\n\t$arrows.append(parts.join('')).appendTo($div);\n\t$div.addClass('has-cycle-arrows');\n}\n\nThe arrow array could be placed inside the plugin settings to allow for localisation.\n\nPagination\n\nThe Cycle plugin creates its own HTML for the pagination of the slideshow. All our plugin needs to do is create the list and selector to use. This snippet creates the pagination container and appends it to our specific slideshow container. It sets the Cycle plugin pager option, restricting it to the specific slideshow using the selector we created at the top of the plugin. Like the previous/next links, a class is added to the slideshow container allowing you to style the slideshow itself differently.\n\n// create the clickable pagination\nif ($$.is('.pagination') && list.length > 1) {\n\toptions.pager = selector + '.cycle-pagination';\n\t$pager = $('
- . Unfortunately this is invalid markup but the code still works.\n\nDemos\n\nWell, that describes all the ins-and-outs of the plugin, but demos make it easier to understand! Viewing the source on the demo page shows some of the combinations you can create with a simple
, a few classes and some thought-out JavaScript.\n\nView the demos \u2192\n\nDecide on defaults\n\nThe slideshow plugin uses the exact same settings as the Cycle plugin, but some are explicitly set within the slideshow plugin when using the classes you have set.\n\nWhen deciding on what functionality is going to be controlled via this class method, be careful to choose your defaults wisely. If all slideshows should auto-play, don\u2019t make this an option \u2014 make the option to stop the auto-play. Similarly, if every slideshow should have previous/next functionality make this the default and expose the ability to remove them with a class such as \u201cno-pagination\u201d.\n\nIn the examples presented on this article I have used a class on each
. You can easily change this to anything you want and simply apply the plugin based on the jQuery selector required.\n\nGrab your images\n\nIf you are using AJAX to load in your images, you can speed up development by deciding on and keeping to a folder structure and naming convention. There are two methods: basing the image path based on the current URL; or based on the src of the image. The first allows a different slideshow on each page, but in many instances a site will have a couple of sets of images and therefore the second method is probably preferred.\n\nMetadata \u2021\n\nA method which allows you to directly modify settings in certain plugins, which also uses the classes from your HTML already exists. This is a jQuery plugin called Metadata. This method allows for finer control over the plugin settings themselves. Some people, however, may dislike the syntax and prefer using normal classes, like above which when sprinkled with a bit more JavaScript allows you to control what you need to control.\n\nThe takeaway\n\nHopefully you have understood not only what goes in to a basic jQuery plugin but also learnt a new and powerful idea which you can apply to other areas of your website.\n\nThe idea can also be applied to other common interfaces such as lightboxes or mapping services such as Google Maps \u2014 for example creating markers based on a list of places, each with different pin icons based the anchor class.", "year": "2009", "author": "Trevor Morris", "author_slug": "trevormorris", "published": "2009-12-06T00:00:00+00:00", "url": "https://24ways.org/2009/front-end-code-reusability-with-css-and-javascript/", "topic": "code"} {"rowid": 11, "title": "JavaScript: Taking Off the Training Wheels", "contents": "JavaScript is the third pillar of front-end web development. Of those pillars, it is both the most powerful and the most complex, so it\u2019s understandable that when 24 ways asked, \u201cWhat one thing do you wish you had more time to learn about?\u201d, a number of you answered \u201cJavaScript!\u201d\n\nThis article aims to help you feel happy writing JavaScript, and maybe even without libraries like jQuery. I can\u2019t comprehensively explain JavaScript itself without writing a book, but I hope this serves as a springboard from which you can jump to other great resources.\n\nWhy learn JavaScript?\n\nSo what\u2019s in it for you? Why take the next step and learn the fundamentals?\n\nConfidence with jQuery\n\nIf nothing else, learning JavaScript will improve your jQuery code; you\u2019ll be comfortable writing jQuery from scratch and feel happy bending others\u2019 code to your own purposes. Writing efficient, fast and bug-free jQuery is also made much easier when you have a good appreciation of JavaScript, because you can look at what jQuery is really doing. Understanding how JavaScript works lets you write better jQuery because you know what it\u2019s doing behind the scenes. When you need to leave the beaten track, you can do so with confidence.\n\nIn fact, you could say that jQuery\u2019s ultimate goal is not to exist: it was invented at a time when web APIs were very inconsistent and hard to work with. That\u2019s slowly changing as new APIs are introduced, and hopefully there will come a time when jQuery isn\u2019t needed.\n\nAn example of one such change is the introduction of the very useful document.querySelectorAll. Like jQuery, it converts a CSS selector into a list of matching elements. Here\u2019s a comparison of some jQuery code and the equivalent without.\n\n$('.counter').each(function (index) {\n $(this).text(index + 1);\n});\n\nvar counters = document.querySelectorAll('.counter');\n[].slice.call(counters).forEach(function (elem, index) {\n elem.textContent = index + 1;\n});\n\nSolving problems no one else has!\n\nWhen you have to go to the internet to solve a problem, you\u2019re forever stuck reusing code other people wrote to solve a slightly different problem to your own. Learning JavaScript will allow you to solve problems in your own way, and begin to do things nobody else ever has.\n\nNode.js\n\nNode.js is a non-browser environment for running JavaScript, and it can do just about anything! But if that sounds daunting, don\u2019t worry: the Node community is thriving, very friendly and willing to help.\n\nI think Node is incredibly exciting. It enables you, with one language, to build complete websites with complex and feature-filled front- and back-ends. Projects that let users log in or need a database are within your grasp, and Node has a great ecosystem of library authors to help you build incredible things. Exciting!\n\nHere\u2019s an example web server written with Node. http is a module that allows you to create servers and, like jQuery\u2019s $.ajax, make requests. It\u2019s a small amount of code to do something complex and, while working with Node is different from writing front-end code, it\u2019s certainly not out of your reach.\n\nvar http = require('http');\nhttp.createServer(function (req, res) {\n res.writeHead(200, {'Content-Type': 'text/plain'});\n res.end('Hello World');\n}).listen(1337);\nconsole.log('Server running at http://localhost:1337/');\n\nGrunt and other website tools\n\nNode has brought in something of a renaissance in tools that run in the command line, like Yeoman and Grunt. Both of these rely heavily on Node, and I\u2019ll talk a little bit about Grunt here.\n\nGrunt is a task runner, and many people use it for compiling Sass or compressing their site\u2019s JavaScript and images. It\u2019s pretty cool. You configure Grunt via the gruntfile.js, so JavaScript skills will come in handy, and since Grunt supports plug-ins built with JavaScript, knowing it unlocks the bucketloads of power Grunt has to offer.\n\nWays to improve your skills\n\nSo you know you want to learn JavaScript, but what are some good ways to learn and improve? I think the answer to that is different for different people, but here are some ideas.\n\nRebuild a jQuery app\n\nConverting a jQuery project to non-jQuery code is a great way to explore how you modify elements on the page and make requests to the server for data. My advice is to focus on making it work in one modern browser initially, and then go cross-browser if you\u2019re feeling adventurous. There are many resources for directly comparing jQuery and non-jQuery code, like Jeffrey Way\u2019s jQuery to JavaScript article.\n\nFind a mentor\n\nIf you think you\u2019d work better on a one-to-one basis then finding yourself a mentor could be a brilliant way to learn. The JavaScript community is very friendly and many people will be more than happy to give you their time. I\u2019d look out for someone who\u2019s active and friendly on Twitter, and does the kind of work you\u2019d like to do. Introduce yourself over Twitter or send them an email. I wouldn\u2019t expect a full tutoring course (although that is another option!) but they\u2019ll be very glad to answer a question and any follow-ups every now and then.\n\nGo to a workshop\n\nMany conferences and local meet-ups run workshops, hosted by experts in a particular field. See if there\u2019s one in your area. Workshops are great because you can ask direct questions, and you\u2019re in an environment where others are learning just like you are \u2014 no need to learn alone!\n\nSet yourself challenges\n\nThis is one way I like to learn new things. I have a new thing that I\u2019m not very good at, so I pick something that I think is just out of my reach and I try to build it. It\u2019s learning by doing and, even if you fail, it can be enormously valuable.\n\nWhere to start?\n\nIf you\u2019ve decided learning JavaScript is an important step for you, your next question may well be where to go from here.\n\nI\u2019ve collected some links to resources I know of or use, with some discussion about why you might want to check a particular site out. I hope this serves as a springboard for you to go out and learn as much as you want.\n\nBeginner\n\nIf you\u2019re just getting started with JavaScript, I\u2019d recommend heading to one of these places. They cover the basics and, in some cases, a little more advanced stuff. They\u2019re all reputable sources (although, I\u2019ve included something I wrote \u2014 you can decide about that one!) and will not lead you astray.\n\n\n\tjQuery\u2019s JavaScript 101 is a great first resource for JavaScript that will give you everything you need to work with jQuery like a pro.\n\tCodecademy\u2019s JavaScript Track is a small but useful JavaScript course. If you like learning interactively, this could be one for you.\n\tHTMLDog\u2019s JavaScript Tutorials take you right through from the basics of code to a brief introduction to newer technology like Node and Angular. [Disclaimer: I wrote this stuff, so it comes with a hazard warning!]\n\tThe tuts+ jQuery to JavaScript mentioned earlier is great for seeing how jQuery code looks when converted to pure JavaScript.\n\n\nGetting in-depth\n\nFor more comprehensive documentation and help I\u2019d recommend adding these places to your list of go-tos.\n\n\n\tMDN: the Mozilla Developer Network is the first place I go for many JavaScript questions. I mostly find myself there via a search, but it\u2019s a great place to just go and browse.\n\tAxel Rauschmayer\u2019s 2ality is a stunning collection of articles that will take you deep into JavaScript. It\u2019s certainly worth looking at.\n\tAddy Osmani\u2019s JavaScript Design Patterns is a comprehensive collection of patterns for writing high quality JavaScript, particularly as you (I hope) start to write bigger and more complex applications.\n\n\nAnd finally\u2026\n\nI think the key to learning anything is curiosity and perseverance. If you have a question, go out and search for the answer, even if you have no idea where to start. Keep going and going and eventually you\u2019ll get there. I bet you\u2019ll learn a whole lot along the way. Good luck!\n\nMany thanks to the people who gave me their time when I was working on this article: Tom Oakley, Jack Franklin, Ben Howdle and Laura Kalbag.", "year": "2013", "author": "Tom Ashworth", "author_slug": "tomashworth", "published": "2013-12-05T00:00:00+00:00", "url": "https://24ways.org/2013/javascript-taking-off-the-training-wheels/", "topic": "code"} {"rowid": 294, "title": "New Tricks for an Old Dog", "contents": "Much of my year has been spent helping new team members find their way around the expansive and complex codebase that is the TweetDeck front-end, trying to build a happy and productive group of people around a substantial codebase with many layers of legacy.\nI\u2019ve loved doing this. Everything from writing new documentation, drawing diagrams, and holding technical architecture sessions teaches you something you didn\u2019t know or exposes an area of uncertainty that you can go work on.\nIn this article, I hope to share some experiences and techniques that will prove useful in your own situation and that you can impress your friends in some new and exciting ways!\nHow do you do, fellow kids?\nTo start with I\u2019d like to introduce you to our JavaScript framework, Flight. Right now it\u2019s used by twitter.com and TweetDeck although, as a company, Twitter is largely moving to React.\nOver time, as we used Flight for more complex interfaces, we found it wasn\u2019t scaling with us.\nComposing components into trees was fiddly and often only applied for a specific parent-child pairing. It seems like an obvious feature with hindsight, but it didn\u2019t come built-in to Flight, and it made reusing components a real challenge.\nThere was no standard way to manage the state of a component; they all did it slightly differently, and the technique often varied by who was writing the code. This cost us in maintainability as you just couldn\u2019t predict how a component would be built until you opened it.\nMaking matters worse, Flight relied on events to move data around the application. Unfortunately, events aren\u2019t good for giving structure to complex logic. They jump around in a way that\u2019s hard to understand and debug, and force you to search your code for a specific string \u2014 the event name\u201a to figure out what\u2019s going on.\nTo find fixes for these problems, we looked around at other frameworks. We like React for it\u2019s simple, predictable state management and reactive re-render flow, and Elm for bringing strict functional programming to everyone.\nBut when you have lots of existing code, rewriting or switching framework is a painful and expensive option. You have to understand how it will interact with your existing code, how you\u2019ll test it alongside existing code, and how it will affect the size and performance of the application. This all takes time and effort!\nInstead of planning a rewrite, we looked for the ideas hidden within other frameworks that we could reapply in our own situation or bring to the tools we already were using.\nBoiled down, what we liked seemed quite simple:\n\nComponent nesting & composition\nEasy, predictable state management\nNormal functions for data manipulation\n\nMaking these ideas applicable to Flight took some time, but we\u2019re in a much better place now. Through persistent trial-and-error, we have well documented, testable and standard techniques for creating complex component hierarchies, updating and reacting to state changes, and passing data around the app.\nWhile the specifics of our situation and Flight aren\u2019t really important, this experience taught me something: \n\nDistill good tech into great ideas. You can apply great ideas anywhere.\n\nYou don\u2019t have to use cool kids\u2019 latest framework, hottest build tool or fashionable language to benefit from them. If you can identify a nugget of gold at the heart of it all, why not use it to improve what you have already?\nTimes, they are a changin\u2019\nApart from stealing ideas from the new and shiny, how can we keep make the most of improved tooling and techniques? Times change and so should the way we write code.\nGoing back in time a bit, TweetDeck used some slightly outmoded tools for building and bundling. Without a transpiler like Babel we were missing out new language features, and without a more advanced build tools like Webpack, every module\u2019s source was encased in AMD boilerplate.\nIn fact, we found ourselves with a mix of both AMD syntaxes:\ndefine([\"lodash\"], function (_) {\n // . . .\n});\n\ndefine(function (require) {\n var _ = require(\"lodash\");\n // . . .\n});\nThis just wouldn\u2019t do. And besides, what we really wanted was CommonJS, or even ES2015 module syntax:\nimport _ from \"lodash\";\nThese days we\u2019re using Babel, Webpack, ES2015 modules and many new language features that make development just\u2026 better. But how did we get there?\nTo explain, I want to introduce you to codemods and jscodeshift.\nA codemod is a large-scale refactor of a whole codebase, often mechanical or repetitive. Think of renaming a module or changing an API like URL(\"...\") to new URL(\"...\").\njscodeshift is a toolkit for running automated codemods, where you express a code transformation using code. The automated codemod operates on each file\u2019s syntax tree \u2013 a data-structure representation of the code \u2014 finding and modifying in place as it goes.\nHere\u2019s an example that renames all instances of the variable foo to bar:\nmodule.exports = function (fileInfo, api) {\n return api\n .jscodeshift(fileInfo.source)\n .findVariableDeclarators('foo')\n .renameTo('bar')\n .toSource();\n};\nIt\u2019s a seriously powerful tool, and we\u2019ve used it to write a series of codemods that:\n\nrename modules,\nunify our use of AMD to a single syntax,\ntransition from one testing framework to another, and\nswitch from AMD to CommonJS.\n\nThese changes can be pretty huge and far-reaching. Here\u2019s an example commit from when we switched to CommonJS:\ncommit 8f75de8fd4c702115c7bf58febba1afa96ae52fc\nDate: Tue Jul 12 2016\n\n Run AMD -> CommonJS codemod\n\n 418 files changed, 47550 insertions(+), 48468 deletions(-)\n\nYep, that\u2019s just under 50k lines changed, tested, merged and deployed without any trouble. AMD be gone!\n\nFrom this step-by-step approach, using codemods to incrementally tweak and improve, we extracted a little codemod recipe for making significant, multi-stage changes:\n\nFind all the existing patterns\nChoose the two most similar\nUnify with a codemod\nRepeat.\n\nFor example:\n\nFor module loading, we had 2 competing AMD patterns plus some use of CommonJS\nThe two AMD syntaxes were the most similar\nWe used a codemod to move to unify the AMD patterns\nLater we returned to AMD to convert it to CommonJS\n\nIt\u2019s worked for us, and if you\u2019d like to know more about codemods then check out Evolving Complex Systems Incrementally by Facebook engineer, Christoph Pojer.\nWelcome aboard!\nAs TweetDeck has gotten older and larger, the amount of things a new engineer has to learn about has exploded. The myriad of microservices that manage our data and their layers of authentication, security and business logic around them make for an overwhelming amount of information to hand to a newbie.\nInspired by Amy\u2019s amazing Guide to the Care and Feeding of Junior Devs, we realised it was important to take time to design our onboarding that each of our new hires go through to make the most of their first few weeks.\nJoining a new company, team, or both, is stressful and uncomfortable. Everything you can do to help a new hire will be valuable to them. So please, take time to design your onboarding!\nAnd as you build up an onboarding process, you\u2019ll create things that are useful for more than just new hires; it\u2019ll force you to write documentation, for example, in a way that\u2019s understandable for people who are unfamiliar with your team, product and codebase. This can lead to more outside contributions: potential contributors feel more comfortable getting set up on your product without asking for help.\nThis is something that\u2019s taken for granted in open source, but somehow I think we forget about it in big companies.\nAfter all, better documentation is just a good thing. You will forget things from time to time, and you\u2019d be surprised how often the \u201cbeginner\u201d docs help!\nFor TweetDeck, we put together system and architecture diagrams, and one-pager explanations of important concepts:\n\nWhat are our dependencies?\nWhere are the potential points of failure?\nWhere does authentication live? Storage? Caching?\nWho owns \u201cX\u201d?\n\n\nOf course, learning continues long after onboarding. The landscape is constantly shifting; old services are deprecated, new APIs appear and what once true can suddenly be very wrong. Keeping up with this is a serious challenge, and more than any one person can track.\nTo address this, we\u2019ve thought hard about our knowledge sharing practices across the whole team. For example, we completely changed the way we do code review.\nIn my opinion, code review is the single most effective practice you can introduce to share knowledge around, and build the quality and consistency of your team\u2019s work. But, if you\u2019re not doing it, here\u2019s my suggestion for getting started:\n\nEvery pull request gets a +1 from someone else.\n\nThat\u2019s all \u2014 it\u2019s very light-weight and easy. Just ask someone to have a quick look over your code before it goes into master.\nAt Twitter, every commit gets a code review. We do a lot of reviewing, so small efficiency and effectiveness improvements make a big difference. Over time we learned some things:\n\nDon\u2019t review for more than hour 1\nKeep reviews smaller than ~400 lines 2\nCode review your own code first 2\n\nAfter an hour, and above roughly 400 lines, your ability to detect issues in a code review starts to decrease. So review little and often. The gaps around lunch, standup and before you head home are ideal. And remember, if someone\u2019s put code up for a review, that review is blocking them doing other work. It\u2019s your job to unblock them.\nOn TweetDeck, we actually try to keep reviews under 250 lines. It doesn\u2019t sound like much, but this constraint applies pressure to make smaller, incremental changes. This makes breakages easier to detect and roll back, and leads to a very natural feature development process that encourages learning and iteration.\nBut the most important thing I\u2019ve learned personally is that reviewing my own code is the best way to spot issues. I try to approach my own reviews the way I approach my team\u2019s: with fresh, critical eyes, after a break, using a dedicated code review tool.\nIt\u2019s amazing what you can spot when you put a new in a new interface around code you\u2019ve been staring at for hours!\nAnd yes, this list features science. The data backs up these conclusions, and if you\u2019d like to learn more about scientific approaches to software engineering then I recommend you buy Making Software: What Really Works, and Why We Believe It. It\u2019s ace.\nFor more dedicated information sharing, we\u2019ve introduced regular seminars for everyone who works on a specific area or technology. It works like this: a team-member shares or teaches something to everyone else, and next time it\u2019s someone else\u2019s turn. Giving everyone a chance to speak, and encouraging a wide range of topics, is starting to produce great results.\nIf you\u2019d like to run a seminar, one thing you could try to get started: run a point at the thing you least understand in our architecture session \u2014 thanks to James for this idea. And guess what\u2026 your onboarding architecture diagrams will help (and benefit from) this!\nMore, please!\nThere\u2019s a few ideas here to get you started, but there are even more in a talk I gave this year called Frontend Archaeology, including a look at optimising for confidence with front-end operations.\nAnd finally, thanks to Amy for proof reading this and to Passy for feedback on the original talk.\n\n\n\n\nDunsmore et al. 2000. Object-Oriented Inspection in the Face of Delocalisation. Beverly, MA: SmartBear Software.\u00a0\u21a9\n\n\nCohen, Jason. 2006. Best Kept Secrets of Peer Code Review. Proceedings of the 22nd ICSE 2000: 467-476.\u00a0\u21a9 \u21a9", "year": "2016", "author": "Tom Ashworth", "author_slug": "tomashworth", "published": "2016-12-18T00:00:00+00:00", "url": "https://24ways.org/2016/new-tricks-for-an-old-dog/", "topic": "code"} {"rowid": 191, "title": "CSS Animations", "contents": "Friend: You should learn how to write CSS!\nMe: \u2026\nFriend: CSS; Cascading Style Sheets. If you\u2019re serious about web design, that\u2019s the next thing you should learn.\nMe: What\u2019s wrong with tags?\n\nThat was 8 years ago. Thanks to the hard work of Jeffrey, Andy, Andy, Cameron, Colly, Dan and many others, learning how to decently markup a website and write lightweight stylesheets was surprisingly easy. They made it so easy even a complete idiot (OH HAI) was able to quickly master it.\n\nAnd then\u2026 nothing. For a long time, it seemed like there wasn\u2019t happening anything in the land of CSS, time stood still. Once you knew the basics, there wasn\u2019t anything new to keep up with. It looked like a great band split, but people just kept re-releasing their music in various \u201cBest Of!\u201d or \u201cRemastered!\u201d albums.\n\nFast forward a couple of years to late 2006. On the official WebKit blog Surfin\u2019 Safari, there\u2019s an article about something called CSS animations. Great new stuff to play with, but only supported by nightly builds (read: very, very beta) of WebKit. In the following months, they release other goodies, like CSS gradients, CSS reflections, CSS masks, and even more CSS animation sexiness. Whoa, looks like the band got back together, found their second youth, and went into overdrive! The problem was that if you wanted to listen to their new albums, you had to own some kind of new high-tech player no one on earth (besides some early adopters) owned.\n\nBack in the time machine. It is now late 2009, close to Christmas. Things have changed. Browsers supporting these new toys are widely available left and right. Even non-techies are using these advanced browsers to surf the web on a daily basis!\n\nEpic win? Almost, but at least this gives us enough reason to start learning how we could use all this new CSS voodoo. On Monday, Natalie Downe showed you a good tutorial on Going Nuts with CSS Transitions. Today, I\u2019m taking it one step further\u2026\n\nHowto: A basic spinner\n\nNo matter how fast internet tubes or servers are, we\u2019ll always need spinners to indicate something\u2019s happening behind the scenes. Up until now, people would go to some site, pick one of the available templates, customize their foreground and background colors, and download a beautiful GIF image.\n\nThere are some downsides to this though:\n\n\n\tIt\u2019s only _semi_-transparent: If you change your mind and pick a slightly different background color, you need to go back to the site, set all the parameters again, and replace your current image. There isn\u2019t even a way to pick an image or gradient as background.\n\tLimited number of frames, probable to keep the file-size as small as possible (don\u2019t forget this thing needs to be loaded before whatever process is finished in the background), and you don\u2019t have that 24 frames per second smoothness.\n\tThis is just too fucking easy. As a front-end code geek, there must be a \u201ccooler\u201d way to do this!\n\n\nWhat do we need to make a spinner with CSS animations? One image, and one element on our webpage we can hook on to. Yes, that\u2019s it. I created a simple transparent PNG that looks it might be a spinner, and for the element on the page, I wrote this piece of genius HTML:\n\n
Please wait while we do what we do best.
\n\nLooks semantic enough to me! Here\u2019s the basic HTML I\u2019m using to position the element in the center of the screen, and make the text inside it disappear:\n\n#spinner {\n\tposition: absolute;\n\ttop: 50%;\n\tleft: 50%;\n\tmargin: -100px 0 0 -100px;\n\theight: 200px;\n\twidth: 200px;\n\ttext-indent: 250px;\n\twhite-space: nowrap;\n\toverflow: hidden;\n}\n\nCool, but now we don\u2019t see anything. Let\u2019s pull rabbit number one out of the hat: -webkit-mask-image (accompanied by the previously mentioned transparent PNG image):\n\n#spinner {\n\t...\n\t-webkit-mask-image: url(../img/spinner.png);\n}\n\nBy now you should be feeling like a magician already. Oh, wait, we still have a blank screen, looks like we left something in the hat (tip: not rabbit droppings):\n\n#spinner {\n\t...\n\t-webkit-mask-image: url(../img/spinner.png);\n\tbackground-color: #000;\n}\n\nNice! What we\u2019ve done right here is telling the element to clip onto the PNG. It\u2019s a lot like clipping layers in Photoshop. So, spinners, they move, right? Into the hat again, and look what we pull out this time: CSS animations!\n\n#spinner {\n\t...\n\t-webkit-mask-image: url(../img/spinner.png);\n\tbackground-color: #000;\n\t-webkit-animation-name: spinnerRotate;\n\t-webkit-animation-duration: 2s;\n\t-webkit-animation-iteration-count: infinite;\n\t-webkit-animation-timing-function: linear;\n}\n\nSome explanation:\n\n\n\t-webkit-animation-name: Name of the animation we\u2019ll be defining later.\n\t-webkit-animation-duration: The timespan of the animation.\n\t-webkit-animation-iteration-count: Repeat once, a defined number of times or infinitely?\n\t-webkit-animation-timing-function: Linear is the one you\u2019ll be using mostly. Other options are ease-in, ease-out, ease-in-out\u2026\n\n\nLet\u2019s define spinnerRotate:\n\n@-webkit-keyframes spinnerRotate {\n\tfrom {\n\t\t-webkit-transform:rotate(0deg);\n\t}\n\tto {\n\t\t-webkit-transform:rotate(360deg);\n\t}\n}\n\nEn Anglais: Rotate #spinner starting at 0 degrees, ending at 360 degrees, over a timespan of 2 seconds, at a constant speed, and keep repeating this animation forever.\n\nThat\u2019s it! See it in action on the demo page.\n\nNote: these examples only work when you\u2019re using a WebKit-based browser like Safari, Mobile Safari or Google Chrome. I\u2019m confident though that Mozilla and Opera will try their very best catching up with all this new CSS goodness soon.\n\nWhen looking at this example, you see the possibilities are endless. Another advantage is you can change the look of it entirely by only changing a couple of lines of CSS, instead of re-creating and re-downloading the image from some website smelling like web 2.0 gone bad. I made another demo that shows how great it is to be able to change background and foreground colors (even on the fly!).\n\nSo there you have it, a smoothly animated, fully transparent and completely customizable spinner. Cool? I think so. (Ladies?)\n\nBut you can do a lot more with CSS animations than just create pretty spinners. Since I was fooling around with it anyway, I decided to test how far you can push this, space is the final limit, right?\n\nConclusion\n\nCSS has never been more exciting than it is right now. I\u2019m even prepared to say CSS is \u201ccool\u201d again, both for the more experienced front-end developers as for the new designers discovering CSS every day now.\n\nBut\u2026\n\nRemember when Javascript became popular? Remember when Flash became popular? Every time we\u2019re been given new toys, some people aren\u2019t ashamed to use it in a way you can barely call constructive. I\u2019m thinking of Geocities websites, loaded with glowing blocks of text, moving images, bad color usage\u2026 In the wise words of Stan Lee: With great power there must also come great responsibility! A sprinkle of CSS animations is better than a bucket load. Apply with care.", "year": "2009", "author": "Tim Van Damme", "author_slug": "timvandamme", "published": "2009-12-15T00:00:00+00:00", "url": "https://24ways.org/2009/css-animations/", "topic": "code"} {"rowid": 202, "title": "Design Systems and CSS Grid", "contents": "Recently, my client has been looking at creating a few new marketing pages for their website. They currently have a design system in place but they\u2019re looking to push this forward into 2018 with some small and possibly some larger changes.\nTo start with we are creating a couple of new marketing pages. As well as making use of existing components within the design systems component library there are a couple of new components. Looking at the first couple of sketch files I felt this would be a great opportunity to use CSS Grid, to me the newer components need to be laid out on that page and grid would help with this perfectly.\n\nAs well as this layout of the new components and the text within it, imagery would be used that breaks out of the grid and pushes itself into the spaces where the text is aligned.\nThe existing grid system\nWhen the site was rebuilt in 2015 the team decided to make use of Sass and Susy, a \u201clightweight grid-layout engine using Sass\u201d. It was built separating the grid system from the components that would be laid out on the page with a container, a row, an optional column, and a block.\nTo make use of the grid system on a page for a component that would take the full width of the row you would have to write something like this:\n\n\nUsing a grid system similar to this can easily create quite the tag soup. It could fill the HTML full of divs that may become complex to understand and difficult to edit.\nAlthough there is this reliance on several\n\n\n\n\n \n\ns to lay out the components on a page it does allow a tidy way to place the component code within that page. It abstracts the layout of the page to its own code, its own system, so the components can \u2018fit\u2019 where needed.\nThe requirements of the new grid system\nMoving forward I set myself some goals for what I\u2019d like to have achieved in this new grid system:\nIt needs to behave like the existing grid systems\nWe are not ripping up the existing grid system, it would be too much work, for now, to retrofit all of the existing components to work in a grid that has a different amount of columns, and spacing at various viewport widths.\nAllow full-width components\nCurrently the grid system is a 14 column grid that becomes centred on the page when viewport is wide enough. We have, in the past, written some CSS that would allow for a full-width component, but his had always felt like a hack. We want the option to have a full-width element as part of the new grid system, not something that needs CSS to fight against.\nLess of a tag soup\nIdeally we want to end up writing less HTML to layout the page. Although the existing system can be quite clear as to what each element is doing, it can also become a little laborious in working out what each grid row or block is doing where.\nI would like to move the layout logic to CSS as much as is possible, potentially creating some utility classes or additional \u2018layout classes\u2019 for the components.\nEasier for people to use and author\nWith many people using the existing design systems codebase we need to create a new grid system that is as easy or easier to use than the existing one. I think and hope this would be helped by removing as manys as needed and would require new documentation and examples, and potentially some initial training.\nSeparating layout from style\nThere still needs to be a separation of layout from the styles for the component. To allow for the component itself to be placed wherever needed in the page we need to make sure that the CSS for the layout is a separate entity to the CSS for that styling.\nWith these base requirements I took to CodePen and started working on some throwaway code to get started.\nMaking the new grid(s)\nThe Full-Width Grid\nTo start with I created a grid that had three columns, one for the left, one for the middle, and one for the right. This would give the full-width option to components.\nThankfully, one of Rachel Andrew\u2019s many articles on Grid discussed this exact requirement of the new grid system to break out with Grid.\nI took some of the code in the examples and edited to make grid we needed.\n.container {\n display: grid;\n grid-template-columns:\n [full-start]\n minmax(.75em, 1fr)\n [main-start]\n minmax(0, 1008px)\n [main-end]\n minmax(.75em, 1fr)\n [full-end];\n}\nWe are declaring a grid, we have four grid column lines which we name and we define how the three columns they create react to the viewport width. We have a left and right column that have a minimum of 12px, and a central column with a maximum width of 1008px.\nBoth left and right columns fill up any additional space if the viewport is wider that 1032px wide. We are also not declaring any gutters to this grid, the left and right columns would act as gutters at smaller viewports.\nAt this point I noticed that older versions of Sass cannot parse the brackets in this code. To combat this I used Sass\u2019 unquote method to wrap around the value of the grid-template-column.\n.container {\n display: grid;\n grid-template-columns:\n unquote(\"\n [full-start]\n minmax(.75em, 1fr)\n [main-start]\n minmax(0, 1008px)\n [main-end]\n minmax(.75em, 1fr)\n [full-end]\n \");\n}\nThe existing codebase makes use of Sass variables, mixins and functions so to remove that would be a problem, but luckily the version of Sass used is up-to-date (note: example CodePens will be using CSS).\nThe initial full-width grid displays on a webpage as below:\n\nThe 14 column grid\nI decided to work out the 14 column grid as a separate prototype before working out how it would fit within the full-width grid. This grid is very similar to the 12 column grids that have been used in web design. Here we need 14 columns with a gutter between each one.\nAlong with the many other resources on Grid, Mozilla\u2019s MDN site had a page on common layouts using CSS Grid. This gave me the perfect CSS I needed to create my grid and I edited it as required:\n.inner {\n display: grid;\n grid-template-columns: repeat(14, [col-start] 1fr);\n grid-gap: .75em;\n}\nWe, again, are declaring a grid, and we are splitting up the available space by creating 14 columns with 1 fr-unit and giving each one a starting line named col-start.\nThis grid would display on web page as below:\n\nBringing the grids together\nNow that we have got the two grids we need to help fulfil our requirements we need to put them together so that they are actually we we need.\nThe subgrid\nThere is no subgrid in CSS, yet. To workaround this for the new grid system we could nest the 14 column grid inside the full-width grid.\nIn the HTML we nest the 14 column inner grid inside the full-width container.\n\n\nSo that the inner knows where to be laid out within the container we tell it what column to start and end with, with this code it would be the start and end of the main column.\n.inner {\n display: grid;\n grid-column: main-start / main-end;\n grid-template-columns: repeat(14, [col-start] 1fr);\n grid-gap: .75em;\n}\nThe CSS for the container remains unchanged.\n\nThis works, but we have added another div to our HTML. One of our requirements is to try and remove the potential for tag soup.\nThe faux subgrid subgrid\nI wanted to see if it would be possible to place the CSS for the 14 column grid within the CSS for the full-width grid. I replaced the CSS for the main grid and added the grid-column-gap to the .container.\n.container {\n display: grid;\n grid-gap: .75em;\n grid-template-columns:\n [full-start]\n minmax(.75em, 1fr)\n [main-start]\n repeat(14, [col-start] 1fr)\n [main-end]\n minmax(.75em, 1fr)\n [full-end];\n}\nWhat this gave me was a 16 column grid. I was unable to find a way to tell the main grid, the grid betwixt main-start and main-end to be a maximum of 1008px as required.\n\nI trawled the internet to find if it was possible to create our main requirement, a 14 column grid which also allows for full-width components. I found that we could not reverse minmax to minmax(1fr, 72px) as 1fr is not allowed as a minimum if there is a maximum. I tried working out if we could make the min larger than its max but in minmax it would be ignored.\nI was struggling, I was hoping for a cleaner version of the grid system we currently use but getting to the point where needing that extra\n\nwould be a necessity.\nAt 3 in the morning, when I was failing to get to sleep, my mind happened upon an question: \u201cCould you use calc?\u201d\nAt some point I drifted back to sleep so the next day I set upon seeing if this was possible. I knew that the maximum width of the central grid needed to be 1008px. The left and right columns needed to be however many pixels were left in the viewport divided by 2. In CSS it looked like I would need to use calc twice. The first time to takeaway 1008px from 100% of the viewport width and the second to divide that result by 2.\ncalc(calc(100% - 1008px) / 2)\nThe CSS above was part of the value that I would need to include in the declaration for the grid.\n.container {\n display: grid;\n grid-gap: .75em;\n grid-template-columns:\n [full-start]\n minmax(calc(calc(100% - 1008px) / 2), 1fr)\n [main-start]\n repeat(14, [col-start] 1fr)\n [main-end]\n minmax(calc(calc(100% - 1008px) / 2), 1fr)\n [full-end];\n}\nWe have created the grid required. A full-width grid, with a central 14 column grid, using fewerelements.\n\nSee the Pen Design Systems and CSS Grid, 6 by Stuart Robson (@sturobson) on CodePen.\n\nSuccess!\nProgressive enhancement\nNow that we have created the grid system required we need to back-track a little.\nNot all browsers support Grid, over the last 9 months or so this has gotten a lot better. However there will still be browsers that visit that potentially won\u2019t have support. The effort required to make the grid system fall back for these browsers depends on your product or sites browser support.\n\nTo determine if we will be using Grid or not for a browser we will make use of feature queries. This would mean that any version of Internet Explorer will not get Grid, as well as some mobile browsers and older versions of other browsers.\n@supports (display: grid) {\n /* Styles for browsers that support Grid */\n}\nIf a browser does not pass the requirements for @supports we will fallback to using flexbox where possible, and if that is not supported we are happy for the page to be laid out in one column.\nA website doesn\u2019t have to look the same in every browser after all.\nA responsive grid\nWe started with the big picture, how the grid would be at a large viewport and the grid system we have created gets a little silly when the viewport gets smaller.\nAt smaller viewports we have a single column layout where every item of content, every component stacks atop each other. We don\u2019t start to define a grid before we the viewport gets to 700px wide. At this point we have an 8 column grid and if the viewport gets to 1100px or wider we have our 14 column grid.\n/*\n * to start with there is no 'grid' just a single column\n */\n.container {\n padding: 0 .75em;\n}\n\n/*\n * when we get to 700px we create an 8 column grid with\n * a left and right area to breakout of the grid.\n */\n@media (min-width: 700px) {\n .container {\n display: grid;\n grid-gap: .75em;\n grid-template-columns:\n [full-start]\n minmax(calc(calc(100% - 1008px) / 2), 1fr)\n [main-start]\n repeat(8, [col-start] 1fr)\n [main-end]\n minmax(calc(calc(100% - 1008px) / 2), 1fr)\n [full-end];\n padding: 0;\n }\n}\n\n/*\n * when we get to 1100px we create an 14 column grid with\n * a left and right area to breakout of the grid.\n */\n@media (min-width: 1100px) {\n .container {\n grid-template-columns:\n [full-start]\n minmax(calc(calc(100% - 1008px) / 2), 1fr)\n [main-start]\n repeat(14, [col-start] 1fr)\n [main-end]\n minmax(calc(calc(100% - 1008px) / 2), 1fr)\n [full-end];\n }\n}\nBeing explicit in creating this there is some repetition that we could avoid, we will define the number of columns for the inner grid by using a Sass variable or CSS custom properties (more commonly termed as CSS variables).\nLet\u2019s use CSS custom properties. We need to declare the variable first by adding it to our stylesheet.\n:root {\n --inner-grid-columns: 8;\n}\nWe then need to edit a few more lines. First make use of the variable for this line.\nrepeat(8, [col-start] 1fr)\n/* replace with */\nrepeat(var(--inner-grid-columns), [col-start] 1fr)\nThen at the 1100px breakpoint we would only need to change the value of the \u2014inner-grid-columns value.\n@media (min-width: 1100px) {\n .container {\n grid-template-columns:\n [full-start]\n minmax(calc(calc(100% - 1008px) / 2), 1fr)\n [main-start]\n repeat(14, [col-start] 1fr)\n [main-end]\n minmax(calc(calc(100% - 1008px) / 2), 1fr)\n [full-end];\n }\n}\n/* replace with */\n@media (min-width: 1100px) {\n .container {\n --inner-grid-columns: 14;\n }\n}\nSee the Pen Design Systems and CSS Grid, 8 by Stuart Robson (@sturobson) on CodePen.\n\nThe final grid system\nWe have finally created our new grid for the design system. It stays true to the existing grid in place, adds the ability to break-out of the grid, removes athat could have been needed for the nested 14 column grid.\nWe can move on to the new component.\nCreating a new component\nBack to the new components we are needing to create.\n\nTo me there are two components one of which is a slight variant of the first. This component contains a title, subtitle, a paragraph (potentially paragraphs) of content, a list, and a call to action.\nTo start with we should write the HTML for the component, something like this:\n\n \n \n \nTo place the component on the existing grid is fine, but as child elements are not affected by the container grid we need to define another grid for the features component.\nAs the grid doesn\u2019t get invoked until 700px it is possible to negate the need for a media query.\n.features {\n grid-column: col-start 1 / span 6;\n}\n\n@supports (display: grid) {\n @media (min-width: 1100px) {\n .features {\n grid-column-end: 9;\n }\n }\n}\nWe can also avoid duplication of declarations by making use of the grid-column shorthand and longhand. We need to write a little more CSS for the variant component, the one that will sit on the right side of the page too.\n.features:nth-of-type(even) {\n grid-column-start: 4;\n grid-row: 2;\n}\n\n@supports (display: grid) {\n @media (min-width: 1100px) {\n .features:nth-of-type(even) {\n grid-column-start: 9;\n grid-column-end: 16;\n }\n }\n}\nWe cannot place the items within features on the container grid as they are not direct children. To make this work we have to define a grid for the features component.\nWe can do this by defining the grid at the first breakpoint of 700px making use of CSS custom properties again to define how many columns there will need to be.\n.features {\n grid-column: col-start 1 / span 6;\n --features-grid-columns: 5;\n}\n\n@supports (display: grid) {\n @media (min-width: 700px) {\n .features {\n display: grid;\n grid-gap: .75em;\n grid-template-columns: repeat(var(--features-grid-columns), [col-start] 1fr);\n }\n }\n}\n\n@supports (display: grid) {\n @media (min-width: 1100px) {\n .features {\n grid-column-end: 9;\n --features-grid-columns: 7;\n }\n }\n}\nSee the Pen Design Systems and CSS Grid, 10 by Stuart Robson (@sturobson) on CodePen.\n\nLaying out the parts\nLooking at the spec and reading several articles I feel there are two ways that I could layout the text of this component on the grid.\nWe could use the grid-column shorthand that incorporates grid-column-start and grid-column-end or we can make use of grid-template-areas.\ngrid-template-areas allow for a nice visual way of representing how the parts of the component would be laid out. We can take the the mock of the features on the grid and represent them in text in our CSS.\n\nWithin the .features rule we can add the relevant grid-template-areas value to represent the above.\n.features {\n display: grid;\n grid-template-columns: repeat(var(--features-grid-columns), [col-start] 1fr);\n grid-template-areas:\n \". title title title title title title\"\n \". subtitle subtitle subtitle subtitle subtitle . \"\n \". content content content content . . \"\n \". list list list . . . \"\n \". . . . link link link \";\n}\n\nIn order to make the variant of the component we would have to create the grid-template-areas for that component too.\nWe then need to tell each element of the component in what grid-area it should be placed within the grid.\n.features__title { grid-area: title; }\n.features__subtitle { grid-area: subtitle; }\n.features__content { grid-area: content; }\n.features__list { grid-area: list; }\n.features__link { grid-area: link; }\nSee the Pen Design Systems and CSS Grid, 12 by Stuart Robson (@sturobson) on CodePen.\n\nThe other way would be to use the grid-column shorthand and the grid-column-start and grid-column-end we have used previously.\n.features .features__title {\n grid-column: col-start 2 / span 6;\n}\n.features .features__subtitle {\n grid-column: col-start 2 / span 5;\n}\n.features .features__content {\n grid-column: col-start 2 / span 4;\n}\n.features .features__list {\n grid-column: col-start 2 / span 4;\n}\n.features .features__link {\n grid-column: col-start 5 / span 3;\n}\nFor the variant of the component we can use the grid-column-start property as it will inherit the span defined in the grid-column shorthand.\n.features:nth-of-type(even) .features__title {\n grid-column-start: col-start 1;\n}\n.features:nth-of-type(even) .features__subtitle {\n grid-column-start: col-start 1;\n}\n.features:nth-of-type(even) .features__content {\n grid-column-start: col-start 3;\n}\n.features:nth-of-type(even) .features__list {\n grid-column-start: col-start 3;\n}\n.features:nth-of-type(even) .features__link {\n grid-column-start: col-start 1;\n}\nSee the Pen Design Systems and CSS Grid, 14 by Stuart Robson (@sturobson) on CodePen.\n\nI think, for now, we will go with using grid-column properties rather than grid-template-areas. The repetition needed for creating the variant feels too much where we can change the grid-column-start instead, keeping the components elements layout properties tied a little closer to the elements rather than the grid.\nSome additional decisions\nThe current component library has existing styles for titles, subtitles, lists, paragraphs of text and calls to action. These are name-spaced so that they shouldn\u2019t clash with any other components. Looking forward there will be a chance that other products adopt the component library, but they may bring their own styles for titles, subtitles, etc.\nOne way that we could write our code now for that near future possibility is to make sure our classes are working hard. Using class-attribute selectors we can target part of the class attributes that we know the elements in the component will have using *=.\n.features [class*=\"title\"] {\n grid-column: col-start 2 / span 6;\n}\n.features [class*=\"subtitle\"] {\n grid-column: col-start 2 / span 5;\n}\n.features [class*=\"content\"] {\n grid-column: col-start 2 / span 4;\n}\n.features [class*=\"list\"] {\n grid-column: col-start 2 / span 4;\n}\n.features [class*=\"link\"] {\n grid-column: col-start 5 / span 3;\n}\nSee the Pen Design Systems and CSS Grid, 15 by Stuart Robson (@sturobson) on CodePen.\n\nAlthough the component we have created have a title, subtitle, paragraphs, a list, and a call to action there may be a time where one ore more of these is not required or available. One thing I found out is that if the element doesn\u2019t exist then grid will not create space for it. This may be obvious, but it can be really helpful in making a nice malleable component.\nWe have only looked at columns, as existing components have their own spacing for the vertical rhythm of the page we don\u2019t really want to have them take up equal space in the component and just take up the space as needed. We can do this by adding grid-auto-rows: min-content; to our .features. This is useful if you also need your component to take up a height that is more than the component itself.\nThe grid of the future\nFrom prototyping this new grid and components in CSS Grid, I\u2019ve found it a fantastic way to reimagine how we can create a layout or grid system for our sites. It gives us options to create the same layouts in differing ways that could suit a project and its needs.\nIt allows us to carry on \u2013 if we choose to \u2013 using a-based grid but swapping out floats for CSS Grid or to tie it to our components so they have specific places to go depending on what component is being used. Or we could have several \u2018grid components\u2019 in our design system that we could use to layout various components throughout a page.\nIf you find yourself tasked with creating some new components for your design system try it. If you are starting from scratch I believe you really should start with CSS Grid for your layout.\nIt really feels like the possibilities are endless in terms of layout for the web.\nResources\nHere are just a few resources I have pawed over these last few weeks whilst getting acquainted with CSS Grid.\n\nA collection of CodePens from this article\nGrid by Example from Rachel Andrew\nA Complete Guide to CSS Grid on Codrops from Hui Jing Chen\nRachel Andrew\u2019s Blog Archive tagged: cssgrid\nCSS Grid Layout Examples\nMDN\u2019s CSS Grid Layout\nA Complete Guide to Grid from CSS-Tricks\nCSS Grid Layout Module Level 1 Specification", "year": "2017", "author": "Stuart Robson", "author_slug": "stuartrobson", "published": "2017-12-12T00:00:00+00:00", "url": "https://24ways.org/2017/design-systems-and-css-grid/", "topic": "code"} {"rowid": 157, "title": "Capturing Caps Lock", "contents": "One of the more annoying aspects of having to remember passwords (along with having to remember loads of them) is that if you\u2019ve got Caps Lock turned on accidentally when you type one in, it won\u2019t work, and you won\u2019t know why. Most desktop computers alert you in some way if you\u2019re trying to enter your password to log on and you\u2019ve enabled Caps Lock; there\u2019s no reason why the web can\u2019t do the same. What we want is a warning \u2013 maybe the user wants Caps Lock on, because maybe their password is in capitals \u2013 rather than something that interrupts what they\u2019re doing. Something subtle.\n\nBut that doesn\u2019t answer the question of how to do it. Sadly, there\u2019s no way of actually detecting whether Caps Lock is on directly. However, there\u2019s a simple work-around; if the user presses a key, and it\u2019s a capital letter, and they don\u2019t have the Shift key depressed, why then they must have Caps Lock on! Simple. \n\nDOM scripting allows your code to be notified when a key is pressed in an element; when the key is pressed, you get the ASCII code for that key. Capital letters, A to Z, have ASCII codes 65 to 90. So, the code would look something like:\n\non a key press\n\tif the ASCII code for the key is between 65 and 90 *and* if shift is pressed\n\t\twarn the user that they have Caps Lock on, but let them carry on\n\tend if\nend keypress\n\nThe actual JavaScript for this is more complicated, because both event handling and keypress information differ across browsers. Your event handling functions are passed an event object, except in Internet Explorer where you use the global event object; the event object has a which parameter containing the ASCII code for the key pressed, except in Internet Explorer where the event object has a keyCode parameter; some browsers store whether the shift key is pressed in a shiftKey parameter and some in a modifiers parameter. All this boils down to code that looks something like this:\n\nkeypress: function(e) {\n\tvar ev = e ? e : window.event;\n\tif (!ev) {\n\t\treturn;\n\t}\n\tvar targ = ev.target ? ev.target : ev.srcElement;\n\t// get key pressed\n\tvar which = -1;\n\tif (ev.which) {\n\t\twhich = ev.which;\n\t} else if (ev.keyCode) {\n\t\twhich = ev.keyCode;\n\t}\n\t// get shift status\n\tvar shift_status = false;\n\tif (ev.shiftKey) {\n\t\tshift_status = ev.shiftKey;\n\t} else if (ev.modifiers) {\n\t\tshift_status = !!(ev.modifiers & 4);\n\t}\n\n\t// At this point, you have the ASCII code in \u201cwhich\u201d, \n\t// and shift_status is true if the shift key is pressed\n}\n\nThen it\u2019s just a check to see if the ASCII code is between 65 and 90 and the shift key is pressed. (You also need to do the same work if the ASCII code is between 97 (a) and 122 (z) and the shift key is not pressed, because shifted letters are lower-case if Caps Lock is on.)\n\nif (((which >= 65 && which <= 90) && !shift_status) || \n\t((which >= 97 && which <= 122) && shift_status)) {\n\t// uppercase, no shift key\n\t/* SHOW THE WARNING HERE */\n} else {\n\t/* HIDE THE WARNING HERE */\n}\n\nThe warning can be implemented in many different ways: highlight the password field that the user is typing into, show a tooltip, display text next to the field. For simplicity, this code shows the warning as a previously created image, with appropriate alt text. Showing the warning means creating a newtag with DOM scripting, dropping it into the page, and positioning it so that it\u2019s next to the appropriate field. The image looks like this:\n\n\n\nYou know the position of the field the user is typing into (from its offsetTop and offsetLeft properties) and how wide it is (from its offsetWidth properties), so use createElement to make the new img element, and then absolutely position it with style properties so that it appears in the appropriate place (near to the text field). \n\nThe image is a transparent PNG with an alpha channel, so that the drop shadow appears nicely over whatever else is on the page. Because Internet Explorer version 6 and below doesn\u2019t handle transparent PNGs correctly, you need to use the AlphaImageLoader technique to make the image appear correctly.\n\nnewimage = document.createElement('img');\nnewimage.src = \"http://farm3.static.flickr.com/2145/2067574980_3ddd405905_o_d.png\";\nnewimage.style.position = \"absolute\";\nnewimage.style.top = (targ.offsetTop - 73) + \"px\";\nnewimage.style.left = (targ.offsetLeft + targ.offsetWidth - 5) + \"px\";\nnewimage.style.zIndex = \"999\";\nnewimage.setAttribute(\"alt\", \"Warning: Caps Lock is on\");\nif (newimage.runtimeStyle) {\n\t// PNG transparency for IE\n\tnewimage.runtimeStyle.filter += \"progid:DXImageTransform.Microsoft.AlphaImageLoader(src='http://farm3.static.flickr.com/2145/2067574980_3ddd405905_o_d.png',sizingMethod='scale')\";\n}\ndocument.body.appendChild(newimage);\n\nNote that the alt text on the image is also correctly set. Next, all these parts need to be pulled together. On page load, identify all the password fields on the page, and attach a keypress handler to each. (This only needs to be done for password fields because the user can see if Caps Lock is on in ordinary text fields.)\n\nvar inps = document.getElementsByTagName(\"input\");\nfor (var i=0, l=inps.length; i\n\nThe \u201ccreate an image\u201d code from above should only be run if the image is not already showing, so instead of creating a newimage object, create the image and attach it to the password field so that it can be checked for later (and not shown if it\u2019s already showing). For safety, all the code should be wrapped up in its own object, so that its functions don\u2019t collide with anyone else\u2019s functions. So, create a single object called capslock and make all the functions be named methods of the object:\n\nvar capslock = {\n\t... \n\tkeypress: function(e) {\n\t}\n\t...\n}\n\nAlso, the \u201ccreate an image\u201d code is saved into its own named function, show_warning(), and the converse \u201cremove the image\u201d code into hide_warning(). This has the advantage that developers can include the JavaScript library that has been written here, but override what actually happens with their own code, using something like:\n\n\n\n\nAnd that\u2019s all. Simply include the JavaScript library in your pages, override what happens on a warning if that\u2019s more appropriate for what you\u2019re doing, and that\u2019s all you need.\n\n See the script in action.", "year": "2007", "author": "Stuart Langridge", "author_slug": "stuartlangridge", "published": "2007-12-04T00:00:00+00:00", "url": "https://24ways.org/2007/capturing-caps-lock/", "topic": "code"} {"rowid": 201, "title": "Lint the Web Forward With Sonarwhal", "contents": "Years ago, when I was in a senior in college, much of my web development courses focused on two things: the basics like HTML and CSS (and boy, do I mean basic), and Adobe Flash. I spent many nights writing ActionScript 3.0 to build interactions for the websites that I would add to my portfolio. A few months after graduating, I built one website in Flash for a client, then never again. Flash was dying, and it became obsolete in my r\u00e9sum\u00e9 and portfolio. \nThat was my first lesson in the speed at which things change in technology, and what a daunting realization that was as a new graduate looking to enter the professional world. Now, seven years later, I work on the Microsoft Edge team where I help design and build a tool that would have lessened my early career anxieties: sonarwhal. \nSonarwhal is a linting tool, built by and for the web community. The code is open source and lives under the JS Foundation. It helps web developers and designers like me keep up with the constant change in technology while simultaneously teaching how to code better websites. \nIntroducing sonarwhal\u2019s mascot Nellie\nGood web development is hard. It is more than HTML, CSS, and JavaScript: developers are expected to have a grasp of accessibility, performance, security, emerging standards, and more, all while refreshing this knowledge every few months as the web evolves. It\u2019s a lot to keep track of.\n\u00a0\nWeb development is hard \nStaying up-to-date on all this knowledge is one of the driving forces for developing this scanning tool. Whether you are just starting out, are a student, or you have over a decade of experience, the sonarwhal team wants to help you build better websites for all browsers. \nCurrently sonarwhal checks for best practices in five categories: Accessibility, Interoperability, Performance, PWAs, and Security. Each check is called a \u201crule\u201d. You can configure them and even create your own rules if you need to follow some specific guidelines for your project (e.g. validate analytics attributes, title format of pages, etc.). \nYou can use sonarwhal in two ways:\n\nAn online version, that provides a quick and easy way to scan any public website.\nA command line tool, if you want more control over the configuration, or want to integrate it into your development flow.\n\nThe Online Scanner\nThe online version offers a streamlined way to scan a website; just enter a URL and you will get a web page of scan results with a permalink that you can share and revisit at any time.\nThe online version of sonarwal\nWhen my team works on a new rule, we spend the bulk of our time carefully researching each subject, finding sources, and documenting it rather than writing the rule\u2019s code. Not only is it important that we get you the right results, but we also want you to understand why something is failing. Next to each failing rule you\u2019ll find a link to its detailed documentation, explaining why you should care about it, what exactly we are testing, examples that pass and examples that don\u2019t, and useful links to even more in-depth documentation if you are interested in the subject.\nWe hope that between reading the documentation and continued use of sonarwhal, developers can stay on top of best practices. As devs continue to build sites and identify recurring issues that appear in their results, they will hopefully start to automatically include those missing elements or fix those pieces of code that are producing errors. This also isn\u2019t a one-way communication: the documentation is not only available on the sonarwhal site, but also on GitHub for editing so you can help us make it even better!\nA results report\nThe current configuration for the online scanner is very strict, so it might hurt your feelings (it did when I first tested it on my personal website). But you can configure sonarwhal to any level of strictness as well as customize the command line tool to your needs! \nSonarwhal\u2019s CLI\u00a0\nThe CLI gives you full control of sonarwhal: what rules to use, tweaks to them, domains that are out of your control, and so on. You will need the latest node LTS (v8) or Stable (v9) and your favorite package manager, such as npm:\nnpm install -g sonarwhal\nYou can now run sonarwhal from anywhere via:\nsonarwhal https://example.com\nUsing the CLI\nThe configuration is done via a .sonarwhalrc file. When analyzing a site, if no file is available, you will be prompted to answer a series of questions:\n\nWhat connector do you want to use? Connectors are what sonarwhal uses to access a website and gather all the information about the requests, resources, HTML, etc. Currently it supports jsdom, Microsoft Edge, and Google Chrome.\nWhat formatter? This is how you want to see the results: summary, stylish, etc. Make sure to look at the full list. Some are concise for, perfect for a quick build assessment, while others are more verbose and informative.\nDo you want to use the recommended rules configuration? Rules are the things we are validating. Unless you\u2019ve read the documentation and know what you are doing, first timers should probably use the recommended configuration.\nWhat browsers are you targeting? One of the best features of sonarwhal is that rules can adapt their feedback depending on your targeted browsers, suggesting to add or remove things. For example, the rule \u201cHighest Document Mode\u201d will tell you to add the \u201cX-UA-Compatible\u201d header if IE10 or lower is targeted or remove if the opposite is true. \n\nsonarwhal configuration generator questions\nOnce you answer all these questions the scan will start and you will have a .sonarwhalrc file similar to the following:\n{\n \"connector\": {\n \"name\": \"jsdom\",\n \"options\": {\n \"waitFor\": 1000\n }\n },\n \"formatters\": \"stylish\",\n \"rulesTimeout\": 120000,\n \"rules\": {\n \"apple-touch-icons\": \"error\",\n \"axe\": \"error\",\n \"content-type\": \"error\",\n \"disown-opener\": \"error\",\n \"highest-available-document-mode\": \"error\",\n \"validate-set-cookie-header\": \"warning\",\n // ...\n }\n}\nYou should see the scan initiate in the command line and within a few seconds the results should start to appear. Remember, the scan results will look different depending on which formatter you selected so try each one out to see which one you like best. \nsonarwhal results on my website and hurting my feelings \ud83d\udc94\nNow that you have a list of errors, you can get to work improving the site! Note though, that when you scan your website, it scans all the resources on that page and if you\u2019ve added something like analytics or fonts hosted elsewhere, you are unable to change those files. You can configure the CLI to ignore files from certain domains so that you are only getting results for files you are in control of.\nThe documentation should give enough guidance on how to fix the errors, but if it\u2019s insufficient, please help us and suggest edits or contribute back to it. This is a community effort and chances are someone else will have the same question as you.\nWhen I scanned both my websites, sonarwhal alerted me to not having an Apple Touch Icon. If I search on the web as opposed to using the sonarwhal documentation, the first top 3 results give me outdated information: I need to include many different icon sizes. I don\u2019t need to include all the different size icons that target different devices. Declaring one icon sized 180px x 180px will provide a large enough icon for devices and it will scale down as appropriate for people on older devices. \nThe information at the top of the search results isn\u2019t always the correct answer to an issue and we don\u2019t want you to have to search through outdated documentation. As sonarwhal\u2019s capabilities expand, the goal is for it to be the one stop shop for helping preflight your website. \nThe journey up until now and looking forward\n\nOn the Microsoft Edge team, we\u2019re passionate about empowering developers to build great websites. Every day we see so many sites come through our issue tracker. (Thanks for filing those bugs, they help us make Microsoft Edge better and better!) Some issues we see over and over are honest mistakes or outdated \u2018best practices\u2019 that could be avoided, so we built this tool to help everyone help make the web a better place.\nWhen we decided to create sonarwhal, we wanted to create a tool that would help developers write better and more up-to-date code for their websites. We want sonarwhal to be useful to anyone so, early on, we defined three guiding principles we\u2019ve used along the way:\n\nCommunity Driven. We build for the community\u2019s best interests. The web belongs to everyone and this project should too. Not only is it open source, we\u2019ve also donated it to the JS Foundation and have an inclusive governance model that welcomes the collaboration of anyone, individual or company.\nUser Centric. We want to put the user at the center, making sonarwhal configurable for your needs and easy to use no matter what your skill level is.\nCollaborative. We didn\u2019t want to reinvent the wheel, so we collaborated with existing tools and services that help developers build for the web. Some examples are aXe, snyk.io, Cloudinary, etc.\n\nThis is just the beginning and we still have lots to do. We\u2019re hard at work on a backlog of exciting features for future releases, such as:\n\nNew rules for a variety of areas like\u00a0performance,\u00a0accessibility,\u00a0security,\u00a0progressive web apps, and more.\nA plug-in for Visual Studio Code: we want sonarwhal to help you write better websites, and what better moment than when you are in your editor.\nConfiguration options for the online service: as we fine tune the infrastructure, the rule configuration for our scanner is locked, but we look forward to adding CLI customization options here in the near future.\n\nThis is a tool for the web community by the web community so if you are excited about sonarwhal, making a better web, and want to contribute, we have a\u00a0few issues where you might be able to help. Also, don\u2019t forget to check the rest of the\u00a0sonarwhal GitHub organization. PRs are always welcome and appreciated! \nLet us know what you think about the scanner at @NarwhalNellie on Twitter and we hope you\u2019ll help us lint the web forward!", "year": "2017", "author": "Stephanie Drescher", "author_slug": "stephaniedrescher", "published": "2017-12-02T00:00:00+00:00", "url": "https://24ways.org/2017/lint-the-web-forward-with-sonarwhal/", "topic": "code"} {"rowid": 168, "title": "Unobtrusively Mapping Microformats with jQuery", "contents": "Microformats are everywhere. You can\u2019t shake an electronic stick these days without accidentally poking a microformat-enabled site, and many developers use microformats as a matter of course. And why not? After all, why invent your own class names when you can re-use pre-defined ones that give your site extra functionality for free?\n\nNevertheless, while it\u2019s good to know that users of tools such as Tails and Operator will derive added value from your shiny semantics, it\u2019s nice to be able to reuse that effort in your own code.\n\nWe\u2019re going to build a map of some of my favourite restaurants in Brighton. Fitting with the principles of unobtrusive JavaScript, we\u2019ll start with a semantically marked up list of restaurants, then use JavaScript to add the map, look up the restaurant locations and plot them as markers.\n\nWe\u2019ll be using a couple of powerful tools. The first is jQuery, a JavaScript library that is ideally suited for unobtrusive scripting. jQuery allows us to manipulate elements on the page based on their CSS selector, which makes it easy to extract information from microformats.\n\nThe second is Mapstraction, introduced here by Andrew Turner a few days ago. We\u2019ll be using Google Maps in the background, but Mapstraction makes it easy to change to a different provider if we want to later.\n\nGetting Started\n\nWe\u2019ll start off with a simple collection of microformatted restaurant details, representing my seven favourite restaurants in Brighton. The full, unstyled list can be seen in restaurants-plain.html. Each restaurant listing looks like this:\n\n
- \n\t
\n\nSince we\u2019re dealing with a list of restaurants, each hCard is marked up inside a list item. Each restaurant is an organisation; we signify this by placing the classes fn and org on the element surrounding the restaurant\u2019s name (according to the hCard spec, setting both fn and org to the same value signifies that the hCard represents an organisation rather than a person).\n\nThe address information itself is contained within a div of class adr. Note that the HTML element is not suitable here for two reasons: firstly, it is intended to mark up contact details for the current document rather than generic addresses; secondly, address is an inline element and as such cannot contain the paragraphs elements used here for the address information.\n\nA nice thing about microformats is that they provide us with automatic hooks for our styling. For the moment we\u2019ll just tidy up the whitespace a bit; for more advanced style tips consult John Allsop\u2019s guide from 24 ways 2006.\n\n.vcard p {\n\tmargin: 0;\n}\n.adr {\n\tmargin-bottom: 0.5em;\n}\n\nTo plot the restaurants on a map we\u2019ll need latitude and longitude for each one. We can find this out from their address using geocoding. Most mapping APIs include support for geocoding, which means we can pass the API an address and get back a latitude/longitude point. Mapstraction provides an abstraction layer around these APIs which can be included using the following script tag:\n\n\n\nWhile we\u2019re at it, let\u2019s pull in the other external scripts we\u2019ll be using:\n\n\n\n\n\n\nThat\u2019s everything set up: let\u2019s write some JavaScript!\n\nIn jQuery, almost every operation starts with a call to the jQuery function. The function simulates method overloading to behave in different ways depending on the arguments passed to it. When writing unobtrusive JavaScript it\u2019s important to set up code to execute when the page has loaded to the point that the DOM is available to be manipulated. To do this with jQuery, pass a callback function to the jQuery function itself:\n\njQuery(function() {\n\t// This code will be executed when the DOM is ready\n});\n\nInitialising the map\n\nThe first thing we need to do is initialise our map. Mapstraction needs a div with an explicit width, height and ID to show it where to put the map. Our document doesn\u2019t currently include this markup, but we can insert it with a single line of jQuery code:\n\njQuery(function() {\n\t// First create a div to host the map\n\tvar themap = jQuery('').css({\n\t\t'width': '90%',\n\t\t'height': '400px'\n\t}).insertBefore('ul.restaurants');\n});\n\nWhile this is technically just a single line of JavaScript (with line-breaks added for readability) it\u2019s actually doing quite a lot of work. Let\u2019s break it down in to steps:\n\nvar themap = jQuery('')\n\nHere\u2019s jQuery\u2019s method overloading in action: if you pass it a string that starts with a < it assumes that you wish to create a new HTML element. This provides us with a handy shortcut for the more verbose DOM equivalent:\n\nvar themap = document.createElement('div');\nthemap.id = 'themap';\n\nNext we want to apply some CSS rules to the element. jQuery supports chaining, which means we can continue to call methods on the object returned by jQuery or any of its methods:\n\nvar themap = jQuery('').css({\n\t'width': '90%',\n\t'height': '400px'\n})\n\nFinally, we need to insert our new HTML element in to the page. jQuery provides a number of methods for element insertion, but in this case we want to position it directly before theRiddle & Finns
\n\t\n\t\t\n\t12b Meeting House Lane
\n\t\tBrighton, UK
\n\t\tBN1 1HB
\n\tTelephone: +44 (0)1273 323 008
\n\tE-mail: info@riddleandfinns.co.uk
\n- we are using to contain our restaurants. jQuery\u2019s insertBefore() method takes a CSS selector indicating an element already on the page and places the current jQuery selection directly before that element in the DOM.\n\nvar themap = jQuery('').css({\n\t'width': '90%',\n\t'height': '400px'\n}).insertBefore('ul.restaurants');\n\nFinally, we need to initialise the map itself using Mapstraction. The Mapstraction constructor takes two arguments: the first is the ID of the element used to position the map; the second is the mapping provider to use (in this case google ):\n\n// Initialise the map\nvar mapstraction = new Mapstraction('themap','google');\n\nWe want the map to appear centred on Brighton, so we\u2019ll need to know the correct co-ordinates. We can use www.getlatlon.com to find both the co-ordinates and the initial map zoom level.\n\n// Show map centred on Brighton\nmapstraction.setCenterAndZoom(\n\tnew LatLonPoint(50.82423734980143, -0.14007568359375),\n\t15 // Zoom level appropriate for Brighton city centre\n);\n\nWe also want controls on the map to allow the user to zoom in and out and toggle between map and satellite view.\n\nmapstraction.addControls({\n\tzoom: 'large',\n\tmap_type: true\n});\n\nAdding the markers\n\nIt\u2019s finally time to parse some microformats. Since we\u2019re using hCard, the information we want is wrapped in elements with the class vcard. We can use jQuery\u2019s CSS selector support to find them:\n\nvar vcards = jQuery('.vcard');\n\nNow that we\u2019ve found them, we need to create a marker for each one in turn. Rather than using a regular JavaScript for loop, we can instead use jQuery\u2019s each() method to execute a function against each of the hCards.\n\njQuery('.vcard').each(function() {\n\t// Do something with the hCard\n});\n\nWithin the callback function, this is set to the current DOM element (in our case, the list item). If we want to call the magic jQuery methods on it we\u2019ll need to wrap it in another call to jQuery:\n\njQuery('.vcard').each(function() {\n\tvar hcard = jQuery(this);\n});\n\nThe Google maps geocoder seems to work best if you pass it the street address and a postcode. We can extract these using CSS selectors: this time, we\u2019ll use jQuery\u2019s find() method which searches within the current jQuery selection:\n\nvar streetaddress = hcard.find('.street-address').text();\nvar postcode = hcard.find('.postal-code').text();\n\nThe text() method extracts the text contents of the selected node, minus any HTML markup.\n\nWe\u2019ve got the address; now we need to geocode it. Mapstraction\u2019s geocoding API requires us to first construct a MapstractionGeocoder, then use the geocode() method to pass it an address. Here\u2019s the code outline:\n\nvar geocoder = new MapstractionGeocoder(onComplete, 'google');\ngeocoder.geocode({'address': 'the address goes here');\n\nThe onComplete function is executed when the geocoding operation has been completed, and will be passed an object with the resulting point on the map. We just want to create a marker for the point:\n\nvar geocoder = new MapstractionGeocoder(function(result) {\n\tvar marker = new Marker(result.point);\n\tmapstraction.addMarker(marker);\n}, 'google'); \n\nFor our purposes, joining the street address and postcode with a comma to create the address should suffice:\n\ngeocoder.geocode({'address': streetaddress + ', ' + postcode}); \n\nThere\u2019s one last step: when the marker is clicked, we want to display details of the restaurant. We can do this with an info bubble, which can be configured by passing in a string of HTML. We\u2019ll construct that HTML using jQuery\u2019s html() method on our hcard object, which extracts the HTML contained within that DOM node as a string.\n\nvar marker = new Marker(result.point);\nmarker.setInfoBubble(\n\t'
- \n\t
E-Kagen
\n\t\n\t\t\n\t22-23 Sydney Street
\n\t\tBrighton, UK
\n\t\tBN1 4EN
\n\tTelephone: +44 (0)1273 687 068
\n\tLat/Lon: \n\t\t50.827917, \n\t\t-0.137764\n\t
\n \n\nAs before, I used www.getlatlon.com to find the exact locations \u2013 I find satellite view is particularly useful for locating individual buildings.\n\nLatitudes and longitudes are great for machines but not so useful for human beings. We could hide them entirely with display: none, but I prefer to merely de-emphasise them (someone might want them for their GPS unit):\n\n.vcard .geo {\n\tmargin-top: 0.5em;\n\tfont-size: 0.85em;\n\tcolor: #ccc;\n}\n\nIt\u2019s probably a good idea to hide them completely when they\u2019re displayed inside an info bubble:\n\n.bubble .geo {\n\tdisplay: none;\n}\n\nWe can extract the co-ordinates in the same way we extracted the address. Since we\u2019re no longer geocoding anything our code becomes a lot simpler:\n\n$('.vcard').each(function() {\n\tvar hcard = $(this);\n\tvar latitude = hcard.find('.geo .latitude').text();\n\tvar longitude = hcard.find('.geo .longitude').text();\n\tvar marker = new Marker(new LatLonPoint(latitude, longitude));\n\tmarker.setInfoBubble(\n\t\t'
' + hcard.html() + ''\n);\nmapstraction.addMarker(marker);\n\nWe\u2019ve wrapped the bubble in a div with class bubble to make it easier to style. Google Maps can behave strangely if you don\u2019t provide an explicit width for your info bubbles, so we\u2019ll add that to our CSS now:\n\n.bubble {\n\twidth: 300px;\n}\n\nThat\u2019s everything we need: let\u2019s combine our code together:\n\njQuery(function() {\n\t// First create a div to host the map\n\tvar themap = jQuery('').css({\n\t\t'width': '90%',\n\t\t'height': '400px'\n\t}).insertBefore('ul.restaurants');\n\t// Now initialise the map\n\tvar mapstraction = new Mapstraction('themap','google');\n\tmapstraction.addControls({\n\t\tzoom: 'large',\n\t\tmap_type: true\n\t});\n\t// Show map centred on Brighton\n\tmapstraction.setCenterAndZoom(\n\t\tnew LatLonPoint(50.82423734980143, -0.14007568359375),\n\t\t15 // Zoom level appropriate for Brighton city centre\n\t);\n\t// Geocode each hcard and add a marker\n\tjQuery('.vcard').each(function() {\n\t\tvar hcard = jQuery(this);\n\t\tvar streetaddress = hcard.find('.street-address').text();\n\t\tvar postcode = hcard.find('.postal-code').text();\n\t\tvar geocoder = new MapstractionGeocoder(function(result) {\n\t\t\tvar marker = new Marker(result.point);\n\t\t\tmarker.setInfoBubble(\n\t\t\t\t'' + hcard.html() + ''\n\t\t\t);\n\t\t\tmapstraction.addMarker(marker);\n\t\t}, 'google');\t \n\t\tgeocoder.geocode({'address': streetaddress + ', ' + postcode});\n\t});\n});\n\nHere\u2019s the finished code.\n\nThere\u2019s one last shortcut we can add: jQuery provides the $ symbol as an alias for jQuery. We could just go through our code and replace every call to jQuery() with a call to $(), but this would cause incompatibilities if we ever attempted to use our script on a page that also includes the Prototype library. A more robust approach is to start our code with the following:\n\njQuery(function($) {\n\t// Within this function, $ now refers to jQuery\n\t// ...\n});\n\njQuery cleverly passes itself as the first argument to any function registered to the DOM ready event, which means we can assign a local $ variable shortcut without affecting the $ symbol in the global scope. This makes it easy to use jQuery with other libraries.\n\nLimitations of Geocoding\n\nYou may have noticed a discrepancy creep in to the last example: whereas my original list included seven restaurants, the geocoding example only shows five. This is because the Google Maps geocoder incorporates a rate limit: more than five lookups in a second and it starts returning error messages instead of regular results.\n\nIn addition to this problem, geocoding itself is an inexact science: while UK postcodes generally get you down to the correct street, figuring out the exact point on the street from the provided address usually isn\u2019t too accurate (although Google do a pretty good job).\n\nFinally, there\u2019s the performance overhead. We\u2019re making five geocoding requests to Google for every page served, even though the restaurants themselves aren\u2019t likely to change location any time soon. Surely there\u2019s a better way of doing this?\n\nMicroformats to the rescue (again)! The geo microformat suggests simple classes for including latitude and longitude information in a page. We can add specific points for each restaurant using the following markup:\n\n' + hcard.html() + ''\n\t);\n\tmapstraction.addMarker(marker);\n});\n\nAnd here\u2019s the finished geo example.\n\nFurther reading\n\nWe\u2019ve only scratched the surface of what\u2019s possible with microformats, jQuery (or just regular JavaScript) and a bit of imagination. If this example has piqued your interest, the following links should give you some more food for thought.\n\n\n\tThe hCard specification\n\tNotes on parsing hCards\n\tjQuery for JavaScript programmers \u2013 my extended tutorial on jQuery.\n\tDann Webb\u2019s Sumo \u2013 a full JavaScript library for parsing microformats, based around some clever metaprogramming techniques.\n\tJeremy Keith\u2019s Adactio Austin \u2013 the first place I saw using microformats to unobtrusively plot locations on a map. Makes clever use of hEvent as well.", "year": "2007", "author": "Simon Willison", "author_slug": "simonwillison", "published": "2007-12-12T00:00:00+00:00", "url": "https://24ways.org/2007/unobtrusively-mapping-microformats-with-jquery/", "topic": "code"} {"rowid": 249, "title": "Fast Autocomplete Search for Your Website", "contents": "Every website deserves a great search engine - but building a search engine can be a lot of work, and hosting it can quickly get expensive.\nI\u2019m going to build a search engine for 24 ways that\u2019s fast enough to support autocomplete (a.k.a. typeahead) search queries and can be hosted for free. I\u2019ll be using wget, Python, SQLite, Jupyter, sqlite-utils and my open source Datasette tool to build the API backend, and a few dozen lines of modern vanilla JavaScript to build the interface.\n\nTry it out here, then read on to see how I built it.\nFirst step: crawling the data\nThe first step in building a search engine is to grab a copy of the data that you plan to make searchable.\nThere are plenty of potential ways to do this: you might be able to pull it directly from a database, or extract it using an API. If you don\u2019t have access to the raw data, you can imitate Google and write a crawler to extract the data that you need.\nI\u2019m going to do exactly that against 24 ways: I\u2019ll build a simple crawler using wget, a command-line tool that features a powerful \u201crecursive\u201d mode that\u2019s ideal for scraping websites.\nWe\u2019ll start at the https://24ways.org/archives/ page, which links to an archived index for every year that 24 ways has been running.\nThen we\u2019ll tell wget to recursively crawl the website, using the --recursive flag.\nWe don\u2019t want to fetch every single page on the site - we\u2019re only interested in the actual articles. Luckily, 24 ways has nicely designed URLs, so we can tell wget that we only care about pages that start with one of the years it has been running, using the -I argument like this: -I /2005,/2006,/2007,/2008,/2009,/2010,/2011,/2012,/2013,/2014,/2015,/2016,/2017\nWe want to be polite, so let\u2019s wait for 2 seconds between each request rather than hammering the site as fast as we can: --wait 2\nThe first time I ran this, I accidentally downloaded the comments pages as well. We don\u2019t want those, so let\u2019s exclude them from the crawl using -X \"/*/*/comments\".\nFinally, it\u2019s useful to be able to run the command multiple times without downloading pages that we have already fetched. We can use the --no-clobber option for this.\nTie all of those options together and we get this command:\nwget --recursive --wait 2 --no-clobber \n -I /2005,/2006,/2007,/2008,/2009,/2010,/2011,/2012,/2013,/2014,/2015,/2016,/2017 \n -X \"/*/*/comments\" \n https://24ways.org/archives/ \nIf you leave this running for a few minutes, you\u2019ll end up with a folder structure something like this:\n$ find 24ways.org\n24ways.org\n24ways.org/2013\n24ways.org/2013/why-bother-with-accessibility\n24ways.org/2013/why-bother-with-accessibility/index.html\n24ways.org/2013/levelling-up\n24ways.org/2013/levelling-up/index.html\n24ways.org/2013/project-hubs\n24ways.org/2013/project-hubs/index.html\n24ways.org/2013/credits-and-recognition\n24ways.org/2013/credits-and-recognition/index.html\n...\nAs a quick sanity check, let\u2019s count the number of HTML pages we have retrieved:\n$ find 24ways.org | grep index.html | wc -l\n328\nThere\u2019s one last step! We got everything up to 2017, but we need to fetch the articles for 2018 (so far) as well. They aren\u2019t linked in the /archives/ yet so we need to point our crawler at the site\u2019s front page instead:\nwget --recursive --wait 2 --no-clobber \n -I /2018 \n -X \"/*/*/comments\" \n https://24ways.org/\nThanks to --no-clobber, this is safe to run every day in December to pick up any new content.\nWe now have a folder on our computer containing an HTML file for every article that has ever been published on the site! Let\u2019s use them to build ourselves a search index.\nBuilding a search index using SQLite\nThere are many tools out there that can be used to build a search engine. You can use an open-source search server like Elasticsearch or Solr, a hosted option like Algolia or Amazon CloudSearch or you can tap into the built-in search features of relational databases like MySQL or PostgreSQL.\nI\u2019m going to use something that\u2019s less commonly used for web applications but makes for a powerful and extremely inexpensive alternative: SQLite.\nSQLite is the world\u2019s most widely deployed database, even though many people have never even heard of it. That\u2019s because it\u2019s designed to be used as an embedded database: it\u2019s commonly used by native mobile applications and even runs as part of the default set of apps on the Apple Watch!\nSQLite has one major limitation: unlike databases like MySQL and PostgreSQL, it isn\u2019t really designed to handle large numbers of concurrent writes. For this reason, most people avoid it for building web applications.\nThis doesn\u2019t matter nearly so much if you are building a search engine for infrequently updated content - say one for a site that only publishes new content on 24 days every year.\nIt turns out SQLite has very powerful full-text search functionality built into the core database - the FTS5 extension.\nI\u2019ve been doing a lot of work with SQLite recently, and as part of that, I\u2019ve been building a Python utility library to make building new SQLite databases as easy as possible, called sqlite-utils. It\u2019s designed to be used within a Jupyter notebook - an enormously productive way of interacting with Python code that\u2019s similar to the Observable notebooks Natalie described on 24 ways yesterday.\nIf you haven\u2019t used Jupyter before, here\u2019s the fastest way to get up and running with it - assuming you have Python 3 installed on your machine. We can use a Python virtual environment to ensure the software we are installing doesn\u2019t clash with any other installed packages:\n$ python3 -m venv ./jupyter-venv\n$ ./jupyter-venv/bin/pip install jupyter\n# ... lots of installer output\n# Now lets install some extra packages we will need later\n$ ./jupyter-venv/bin/pip install beautifulsoup4 sqlite-utils html5lib\n# And start the notebook web application\n$ ./jupyter-venv/bin/jupyter-notebook\n# This will open your browser to Jupyter at http://localhost:8888/\nYou should now be in the Jupyter web application. Click New -> Python 3 to start a new notebook.\nA neat thing about Jupyter notebooks is that if you publish them to GitHub (either in a regular repository or as a Gist), it will render them as HTML. This makes them a very powerful way to share annotated code. I\u2019ve published the notebook I used to build the search index on my GitHub account. \n\u200b\n\nHere\u2019s the Python code I used to scrape the relevant data from the downloaded HTML files. Check out the notebook for a line-by-line explanation of what\u2019s going on.\nfrom pathlib import Path\nfrom bs4 import BeautifulSoup as Soup\nbase = Path(\"/Users/simonw/Dropbox/Development/24ways-search\")\narticles = list(base.glob(\"*/*/*/*.html\"))\n# articles is now a list of paths that look like this:\n# PosixPath('...24ways-search/24ways.org/2013/why-bother-with-accessibility/index.html')\ndocs = []\nfor path in articles:\n year = str(path.relative_to(base)).split(\"/\")[1]\n url = 'https://' + str(path.relative_to(base).parent) + '/'\n soup = Soup(path.open().read(), \"html5lib\")\n author = soup.select_one(\".c-continue\")[\"title\"].split(\n \"More information about\"\n )[1].strip()\n author_slug = soup.select_one(\".c-continue\")[\"href\"].split(\n \"/authors/\"\n )[1].split(\"/\")[0]\n published = soup.select_one(\".c-meta time\")[\"datetime\"]\n contents = soup.select_one(\".e-content\").text.strip()\n title = soup.find(\"title\").text.split(\" \u25c6\")[0]\n try:\n topic = soup.select_one(\n '.c-meta a[href^=\"/topics/\"]'\n )[\"href\"].split(\"/topics/\")[1].split(\"/\")[0]\n except TypeError:\n topic = None\n docs.append({\n \"title\": title,\n \"contents\": contents,\n \"year\": year,\n \"author\": author,\n \"author_slug\": author_slug,\n \"published\": published,\n \"url\": url,\n \"topic\": topic,\n })\nAfter running this code, I have a list of Python dictionaries representing each of the documents that I want to add to the index. The list looks something like this:\n[\n {\n \"title\": \"Why Bother with Accessibility?\",\n \"contents\": \"Web accessibility (known in other fields as inclus...\",\n \"year\": \"2013\",\n \"author\": \"Laura Kalbag\",\n \"author_slug\": \"laurakalbag\",\n \"published\": \"2013-12-10T00:00:00+00:00\",\n \"url\": \"https://24ways.org/2013/why-bother-with-accessibility/\",\n \"topic\": \"design\"\n },\n {\n \"title\": \"Levelling Up\",\n \"contents\": \"Hello, 24 ways. Iu2019m Ashley and I sell property ins...\",\n \"year\": \"2013\",\n \"author\": \"Ashley Baxter\",\n \"author_slug\": \"ashleybaxter\",\n \"published\": \"2013-12-06T00:00:00+00:00\",\n \"url\": \"https://24ways.org/2013/levelling-up/\",\n \"topic\": \"business\"\n },\n ...\nMy sqlite-utils library has the ability to take a list of objects like this and automatically create a SQLite database table with the right schema to store the data. Here\u2019s how to do that using this list of dictionaries.\nimport sqlite_utils\ndb = sqlite_utils.Database(\"/tmp/24ways.db\")\ndb[\"articles\"].insert_all(docs)\nThat\u2019s all there is to it! The library will create a new database and add a table to it called articles with the necessary columns, then insert all of the documents into that table.\n(I put the database in /tmp/ for the moment - you can move it to a more sensible location later on.)\nYou can inspect the table using the sqlite3 command-line utility (which comes with OS X) like this:\n$ sqlite3 /tmp/24ways.db\nsqlite> .headers on\nsqlite> .mode column\nsqlite> select title, author, year from articles;\ntitle author year \n------------------------------ ------------ ----------\nWhy Bother with Accessibility? Laura Kalbag 2013 \nLevelling Up Ashley Baxte 2013 \nProject Hubs: A Home Base for Brad Frost 2013 \nCredits and Recognition Geri Coady 2013 \nManaging a Mind Christopher 2013 \nRun Ragged Mark Boulton 2013 \nGet Started With GitHub Pages Anna Debenha 2013 \nCoding Towards Accessibility Charlie Perr 2013 \n...\nThis is the results of our Ajax call.
\n![\"\"](\"../images/loaded.gif\")
\n\nPlease be neat\n\nSo we\u2019ve just jammed some meaningless cruft into our DOM. If our script does anything with images this addition could have some unexpected side effects. (Remember The Fly?) So in order to save that poor, unsuspecting element whose innerHTML we just swapped out from sharing Jeff Goldblum\u2019s terrible fate we should tidy up after ourselves. And by using the removeChild method we do just that.\n\nThis is the results of our Ajax call.
\n", "year": "2005", "author": "Shaun Inman", "author_slug": "shauninman", "published": "2005-12-24T00:00:00+00:00", "url": "https://24ways.org/2005/have-your-dom-and-script-it-too/", "topic": "code"}
{"rowid": 298, "title": "First Steps in VR", "contents": "The web is all around us. As web folk, it is our responsibility to consider the impact our work can have. Part of this includes thinking about the future; the web changes lives and if we are building the web then we are the ones making decisions that affect people in every corner of the world. I find myself often torn between wanting to make the right decisions, and just wanting to have fun. To fiddle and play. We all know how important it is to sometimes just try ideas, whether they will amount to much or not. \nI think of these two mindsets as production and prototyping, though of course there are lots of overlap and phases in between. I mention this because virtual reality is currently seen as a toy for rich people, and in some ways at the moment it is. But with WebVR we are able to create interesting experiences with a relatively low entry point. I want us to have open minds, play around with things, and then see how we can use the tools we have at our disposal to make things that will help people.\nEvery year we see articles saying it will be the \u201cyear of virtual reality\u201d, that was especially prevalent this year. 2016 has been a year of progress, VR isn\u2019t quite mainstream but with efforts like Playstation VR and Google Cardboard, we are definitely seeing much more of it. This year also saw the consumer editions of the Oculus Rift and HTC Vive. So it does seem to be a good time for an overview of how to get involved with creating virtual reality on the web.\nWebVR is an API for connecting to devices and retrieving continuous data such as the position and orientation. Unlike the Web Audio API and some other APIs, WebVR does not feel like a framework. You use it however you want, taking the data and using it as you wish. To make it easier, there are plenty of resources such as Three.js, A-Frame and ReactVR that help to make the heavy lifting a bit easier.\nGetting Started with A-Frame\nI like taking the opportunity to learn new things whenever I can. So while planning this article I thought that instead of trying to teach WebGL or even Three.js in a way that is approachable for all, I would create my first project using A-Frame and write about that. This is not a tutorial as such, I just want to show how to go about getting involved with VR. The beauty of A-Frame is that it is very similar to web components, you can just write HTML to build worlds that will automatically work on all the different types of devices. It uses WebGL and WebVR but in such a way that it quite drastically reduces the learning curve. That\u2019s not to say you can\u2019t build complex things, you have complete access to write JavaScript and shaders.\nI\u2019m lazy. Whenever I learn a new language or framework I have found that the best way, personally, for me to learn is to have a project and to copy the starting code from someone else. A project lets you have a good idea of what you want to produce and it means you can ignore a lot of the irrelevant documentation, focussing purely on what you need. That reduces the stress of figuring things out. Copying code also makes it easier, because you know your boilerplate code is working. There\u2019s nothing worse than getting stuck before anything actually works the first time. So I tinker. I take code and I modify it, I play around. It\u2019s fun.\nFor this project I wanted to keep things as simple as possible, so I can easily explain it without the classic \u201cdraw a circle then draw an owl\u201d. I wrote a list of requirements, with some stretch goals that you can give a try yourself if you fancy:\n\nMust work on Google Cardboard at a minimum, because of price\nTherefore, it must not rely on having a controller\nAuto-moving around a maze would be a good example\nMove in direction you look\nStretch goal: Scoring, time until you hit a wall or get stuck in maze\nStretch goal: Levels, so the map doesn\u2019t need to be random\nStretch goal: Snow!\n\nI decided to base this project on an example, Platforms, by Don McCurdy who wrote the really useful aframe-extras. Platforms has random 3D blocks that you can jump onto, going up into the sky. So I took his code and reduced it so that the blocks are randomly spread on the ground. \n\n\n\n \n \n 24 ways \n \n \n\n\n\n \n\n\n\nAs you can see, this is very readable. Especially if you ignore the JavaScript that is used to create the maze. A-Frame (with A-Frame Extras) gives you a lot of power with relatively little to learn. We start with an\n \n\n\n\n \n\n \n\n \n \n which is the container for everything that is going to show up on the screen. There are a few which can be compared to as they are essentially non-semantic containers, able to be used for any purpose. The attributes are used to define functionality, for example the camera attribute sets the entity to function as a camera and kinematic-body makes it collide instead of go through objects. Attributes are also used to set position and sizes, often using JavaScript to dynamically define them.\nStyling\nNow we\u2019ve got the HTML written, we need to style it. To do this we add A-Frame compatible attributes such as color and material. I recommend playing around, you can get some quite impressive effects fairly easily. Originally I wanted a light snowy maze but it ended up being dark and foggy, as I really liked the feeling it gave.\nNote, you will probably need a server running for images to work. You can do this by running python -m \"SimpleHTTPServer\" in the folder where the code is, then go to localhost:8000 in browser.\nTextures\nUnless you are going for a cartoony style, you probably want to find some textures. I found some on textures.com, one image worked well for the walls and the other for the floor.\n\n \nThe![](\"floor.jpg\")
\n ![](\"wall.jpg\")
\nis used to define (as well as preload and cache) all assets, including images, audio and video. As you can see, images in the Asset Management System just use normal img tags. The ids are important here as we can use them later for using the textures. \nTo apply a texture to an object, you create a material. For a simple material where it just shows the image, you set the src to the id selector of the image.\nReplace: \n \nWith:\n \nThis will automatically make the image repeat over the entire floor, in my case filling it with bricks. The walls are pretty much identical, with the slight exception that it is set in JavaScript as they are dynamically defined.\nbox.setAttribute('material', 'src: #texture-wall');\nThat\u2019s it for the textures, for now at least. These will not look completely realistic, as the light will bump off the rectangular wall rather than texture itself. This can be improved by using maps, textures that are used to modify the shape and physical properties of the object. \nLighting\nThe next part of styling is lighting. By using fog and different types of lighting, we are able to add atmospheric details to the game to make it feel that bit more realistic and polished.\nThere are lots of types of light in A-Frame (most coming from Three.js). You can add a light either by using the entity or by attaching a light attribute to any other entity. If there are no lights defined then A-Frame adds some by default so that the scene is always lit.\nTo start with I wanted to light up the scene with a general light, type=\"ambient\", so that the whole game felt slightly dark. I chose to set the light to a reddish colour #92455E. After playing around with intensity I chose 0.4, it added enough light to get the feeling I wanted without it being overly red. I also added a blue skybox ( ), as it looked a bit odd with a white sky.\n \n \nI felt that the maze looked good with a red tinge but it was a bit flat, everything was the same colour and it was a bit dark. So I added a light within the #player entity, this could have been as an attribute but I set it as a child a-light instead. By using type=\"point\" with a high intensity and low distance, it showed close walls as being lighter. It also added a sort-of object to the player, it isn\u2019t a walking human or anything but by moving light where the player is it feels a bit more physical.\n \n\nBy this point it was starting to look decent, so I wanted to add the fog to really give some personality and depth to the maze. To do this I added the fog attribute to the with type=exponential so it looks thicker the further away it is and a mid intensity, so you feel a bit lost but can still see.\n\nI was very happy with this result. It took a lot of playing around with colours and values, which is fun in itself. I highly recommend you take the code (or write your own) and play around with the numbers.\nMovement\nOne of the reasons I decided to use aframe-extras is that it has a few different camera controls built in. As you saw earlier, I am using the universal-controls which gives WASD (keyboard) controls by default. I wanted to make it automatically move in the direction that you\u2019re looking, but I wasn\u2019t quite sure how without rewriting the controls. So I asked Don McCurdy for advice and he very nicely gave me a small snippet of code to get it working.\nAFRAME.registerComponent('automove-controls', {\n init: function () {\n this.speed = 0.1;\n this.isMoving = true;\n this.velocityDelta = new THREE.Vector3();\n },\n isVelocityActive: function () {\n return this.isMoving;\n },\n getVelocityDelta: function () {\n this.velocityDelta.z = this.isMoving ? -speed : 0;\n return this.velocityDelta.clone();\n }\n});\nReplace:\nuniversal-controls\nWith:\nuniversal-controls=\"movementControls: automove, gamepad, keyboard\"\nThis works by creating a component automove-controls that adds auto-move to the player without overriding movement completely. It doesn\u2019t even touch direction, it just checks if isMoving is true then moves the player by the set speed. Components can be creating for adding all kinds of functionality with relative ease. It makes it very powerful for people of all difficulty levels.\nBuilding a map\nCurrently the maze is created randomly, which is great but means there will often be walls that overlap or the player gets trapped with nowhere to go. So to solve this, I decided to use a map editor (Tiled) so that we can create the mazes ourselves. This is a great start towards one of the stretch goals, levels.\nI made the maze in Tiled by finding a random tileset online (we don\u2019t need to actually show the images), I used one tile for the wall and another for the player. Then I exported as a JavaScript file and modified it in my text editor to get rid of everything I didn\u2019t need. I made it so 0 is the path, 1 is the wall and 2 is the player. I then added the script to the HTML, as a separate file so it\u2019s easy to update in the future. \nvar map =\n{\n \"data\":[1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1],\n \"height\":10,\n \"width\":10\n}\n\nAs you can see, this gives a simple 10x10 maze with some dead ends. The player starts in the bottom right corner (my choice, could be anywhere). I rewrote the random platforms code (from Don\u2019s example) to instead loop over the map data and place walls where it is 1 and position the player where data is 2. I set the position so that the origin of the map would be 0,1.5,0. The y axis is in this case the height (ground being 0), but if a wall is positioned at 0 by its centre then some of it is underground. So the y needed to be the height divided by 2.\ndocument.querySelector('a-scene').addEventListener('render-target-loaded', function () {\n var WALL_SIZE = 5,\n WALL_HEIGHT = 3;\n var el = document.querySelector('#walls');\n var wall;\n\n for (var x = 0; x < map.height; x++) {\n for (var y = 0; y < map.width; y++) {\n\n var i = y*map.width + x;\n var position = (x-map.width/2)*WALL_SIZE + ' ' + 1.5 + ' ' + (y-map.height/2)*WALL_SIZE;\n if (map.data[i] === 1) {\n // Create wall\n wall = document.createElement('a-box');\n el.appendChild(wall);\n wall.setAttribute('color', '#fff');\n wall.setAttribute('material', 'src: #texture-wall;');\n wall.setAttribute('width', WALL_SIZE);\n wall.setAttribute('height', WALL_HEIGHT);\n wall.setAttribute('depth', WALL_SIZE);\n wall.setAttribute('position', position);\n wall.setAttribute('static-body', ');\n }\n\n if (map.data[i] === 2) {\n // Set player position\n document.querySelector('#player').setAttribute('position', position);\n }\n\n }\n }\n console.info('Walls added.');\n});\n\nWith this added, it makes it nice and easy to change around the map as well as to add new features. Perhaps you want monsters or objects. Just set the number in the map data and add an if statement to the loop. In the future you could add layers, so multiple things can be in the same position. Or perhaps even make the maze go up the y axis too, with ramps or staircases. There\u2019s a lot you can do with relative ease. As you can see, A-Frame really does reduce the learning curve of 3D and VR on the web.\nIt\u2019s Not All Fun And Games\nA lot of examples of virtual reality are games, including this one. So it is understandable to think that VR is for gaming, but actually that\u2019s just a tiny subset. There are all sorts of applications for VR, including story telling, data visualisation and even meditation.\nThere have been a number of cases where it has been shown virtual reality can help as a tool for therapies:\n\nOxford study finds virtual reality can help treat severe paranoia\nVirtual Reality Therapy for Phobias at the Duke Faculty Practice\nBravemind: Virtual Reality Exposure Therapy at the University of Southern California\n\nThese are just a few examples of where virtual reality is being used around the world to help people feel better and get through some very tough times. There have also been examples of it being used for simulating war zones or medical situations, both as a teaching and journalism tool.\nWrapping Up\nTen years ago, on this very site, Cameron Moll wrote an article explaining the mobile web. He explained how mobile phones with data plans were becoming increasingly common, that WAP 2.0 included the XHTML Mobile Profile meaning it would be familiar with web folk. \u201cThe mobile web is rapidly becoming an XHTML environment, and thus you and I can apply our existing \u201cdesktop web\u201d skills to understand how to develop content for it.\u201d\nWe can look at that and laugh a little, we have come a very long way in the last decade. Even people in developing countries with very little money have mobile phones with access to a web that is far more capable than the \u201cdesktop web\u201d Cameron was referring to.\nSo while I am not saying virtual reality is going to change the world or replace our phones, who knows! We can use our skills as web folk to dabble, we don\u2019t need to learn any new languages. If on the 2026 edition of 24 ways, somebody references this article and looks at how far we have come\u2026 well, let\u2019s hope we have used our skills well and made the world just that little bit better. And if VR is a fad? Well it\u2019s fun\u2026 have a go anyway.", "year": "2016", "author": "Shane Hudson", "author_slug": "shanehudson", "published": "2016-12-11T00:00:00+00:00", "url": "https://24ways.org/2016/first-steps-in-vr/", "topic": "code"} {"rowid": 211, "title": "Automating Your Accessibility Tests", "contents": "Accessibility is one of those things we all wish we were better at. It can lead to a bunch of questions like: how do we make our site better? How do we test what we have done? Should we spend time each day going through our site to check everything by hand? Or just hope that everyone on our team has remembered to check their changes are accessible?\nThis is where automated accessibility tests can come in. We can set up automated tests and have them run whenever someone makes a pull request, and even alongside end-to-end tests, too.\nAutomated tests can\u2019t cover everything however; only 20 to 50% of accessibility issues can be detected automatically. For example, we can\u2019t yet automate the comparison of an alt attribute with an image\u2019s content, and there are some screen reader tests that need to be carried out by hand too. To ensure our site is as accessible as possible, we will still need to carry out manual tests, and I will cover these later.\nFirst, I\u2019m going to explain how I implemented automated accessibility tests on Elsevier\u2019s ecommerce pages, and share some of the lessons I learnt along the way.\nPicking the right tool\nOne of the hardest, but most important parts of creating our automated accessibility tests was choosing the right tool.\nWe began by investigating aXe CLI, but soon realised it wouldn\u2019t fit our requirements. It couldn\u2019t check pages that required a visitor to log in, so while we could test our product pages, we couldn\u2019t test any customer account pages. Instead we moved over to Pa11y. Its beforeScript step meant we could log into the site and test pages such as the order history. \nThe example below shows the how the beforeScript step completes a login form and then waits for the login to complete before testing the page:\nbeforeScript: function(page, options, next) {\n // An example function that can be used to make sure changes have been confirmed before continuing to run Pa11y\n function waitUntil(condition, retries, waitOver) {\n page.evaluate(condition, function(err, result) {\n if (result || retries < 1) {\n // Once the changes have taken place continue with Pa11y testing\n waitOver();\n } else {\n retries -= 1;\n setTimeout(function() {\n waitUntil(condition, retries, waitOver);\n }, 200);\n }\n });\n }\n\n // The script to manipulate the page must be run with page.evaluate to be run within the context of the page\n page.evaluate(function() {\n const user = document.querySelector('#login-form input[name=\"email\"]');\n const password = document.querySelector('#login-form input[name=\"password\"]');\n const submit = document.querySelector('#login-form input[name=\"submit\"]');\n user.value = 'user@example.com';\n password.value = 'password';\n submit.click();\n }, function() {\n // Use the waitUntil function to set the condition, number of retries and the callback\n waitUntil(function() {\n return window.location.href === 'https://example.com';\n }, 20, next);\n });\n}\nThe waitUntil callback allows the test to be delayed until our test user is successfully logged in.\nAnother thing to consider when picking a tool is the type of error messages it produces. aXe groups all elements with the same error together, so the list of issues is a lot easier to read, and it\u2019s easier to identify the most commons problems. For example, here are some elements that have insufficient colour contrast:\nViolation of \"color-contrast\" with 8 occurrences!\nEnsures the contrast between foreground and background colors meets\nWCAG 2 AA contrast ratio thresholds. Correct invalid elements at:\n - #maincontent > .make_your_mark > div:nth-child(2) > p > span > span\n - #maincontent > .make_your_mark > div:nth-child(4) > p > span > span\n - #maincontent > .inform_your_decisions > div:nth-child(2) > p > span > span\n - #maincontent > .inform_your_decisions > div:nth-child(4) > p > span > span\n - #maincontent > .inform_your_decisions > div:nth-child(6) > p > span > span\n - #maincontent > .inform_your_decisions > div:nth-child(8) > p > span > span\n - #maincontent > .inform_your_decisions > div:nth-child(10) > p > span > span\n - #maincontent > .inform_your_decisions > div:nth-child(12) > p > span > span\nFor details, see: https://dequeuniversity.com/rules/axe/2.5/color-contrast\naXe also provides links to their site where they discuss the best way to fix the problem.\nIn comparison, Pa11y lists each individual error which can lead to a very verbose list. However, it does provide helpful suggestions of how to fix problems, such as suggesting an alternative shade of a colour to use:\n\u2022 Error: This element has insufficient contrast at this conformance level.\n Expected a contrast ratio of at least 4.5:1, but text in this element has a contrast ratio of 2.96:1.\n Recommendation: change text colour to #767676.\n \u23a3 WCAG2AA.Principle1.Guideline1_4.1_4_3.G18.Fail\n \u23a3 #maincontent > div:nth-child(10) > div:nth-child(8) > p > span > span\n \u23a3 Featured products:\nIntegrating into our build pipeline\nWe decided the perfect time to run our accessibility tests would be alongside our end-to-end tests. We have a Jenkins job that detects changes to our staging site and then triggers the end-to-end tests, and in turn our accessibility tests. Our Jenkins job retrieves the contents of a GitHub repository containing our Pa11y script file and npm package manifest.\nOnce Jenkins has cloned the repository, it installs any dependencies and executes the tests via:\nnpm install && npm test\nBundling the URLs to be tested into our test script means we don\u2019t have a command line style test where we list each URL we wish to test in the Jenkins CLI. It\u2019s an effective method but can also be cluttered, and obscure which URLs are being tested.\nIn the middle of the office we have a monitor displaying a Jenkins dashboard and from this we can see if the accessibility tests are passing or failing. Everyone in the team has access to the Jenkins logs and when the build fails they can see why and fix the issue.\nFixing the issues\nAs mentioned earlier, Pa11y can generate a long list of areas for improvement which can be very verbose and quite overwhelming. I recommend going through the list to see which issues occur most frequently and fix those first. For example, we initially had a lot of errors around colour contrast, and one shade of grey in particular. By making this colour darker, the number of errors decreased, and we could focus on the remaining issues.\nAnother thing I like to do is to tackle the quick fixes, such as adding alt text to images. These are small things that allow us to make an impact instantly, giving us time to fix more detailed concerns such as addressing tabindex issues, or speaking to our designers about changing the contrast of elements on the site.\nManual testing\nAdding automated tests to check our site for accessibility is great, but as I mentioned earlier, this can only cover 20-50% of potential issues. To improve on this, we need to test by hand too, either by ourselves or by asking others.\nOne way we can test our site is to throw our mouse or trackpad away and interact with the site using only a keyboard. This allows us to check items such as tab order, and ensure menu items, buttons etc. can be used without a mouse. The commands may be different on different operating systems, but there are some great guides online for learning more about these. \nIt\u2019s tempting to add alt text and aria-labels to make errors go away, but if they don\u2019t make any sense, what use are they really? Using a screenreader we can check that alt text accurately represents the image. This is also a great way to double check that our ARIA roles make sense, and that they correctly identify elements and how to interact with them. When testing our site with screen readers, it\u2019s important to remember that not all screen readers are the same and some may interact with our site differently to others. \nConsider asking a range of people with different needs and abilities to test your site, too. People experience the web in numerous ways, be they permanent, temporary or even situational. They may interact with your site in ways you hadn\u2019t even thought about, so this is a good way to broaden your knowledge and awareness.\nTips and tricks\nOne of our main issues with Pa11y is that it may find issues we don\u2019t have the power to solve. A perfect example of this is the one pixel image Facebook injects into our site. So, we wrote a small function to go though such errors and ignore the ones that we cannot fix.\nconst test = pa11y({\n ....\n hideElements: '#ratings, #js-bigsearch',\n ...\n});\n\nconst ignoreErrors: string[] = [\n ' ![](\"https://books.google.com/intl/en/googlebooks/images/gbs_preview_button1.gif\")
',\n '',\n ''\n ];\n const filterResult = result => {\n if (ignoreErrors.indexOf(result.context) > -1) {\n return false;\n }\n return true;\n };\nInitially we wanted to focus on fixing the major problems, so we added a rule to ignore notices and warnings. This made the list or errors much smaller and allowed us focus on fixing major issues such as colour contrast and missing alt text. The ignored notices and warnings can be added in later after these larger issues have been resolved. \nconst test = pa11y({\n ignore: [\n 'notice',\n 'warning'\n ],\n...\n});\nJenkins gotchas\nWhile using Jenkins we encountered a few problems. Sometimes Jenkins would indicate a build had passed when in reality it had failed. This was because Pa11y had timed out due to PhantomJS throwing an error, or the test didn\u2019t go past the first URL. Pa11y has recently released a new beta version that uses headless Chrome instead of PhantomJS, so hopefully these issues will less occur less often. \nWe tried a few approaches to solve these issues. First we added error handling, iterating over the array of test URLs so that if an unexpected error happened, we could catch it and exit the process with an error indicating that the job had failed (using process.exit(1)). \nfor (const url of urls) {\n try {\n console.log(url);\n let urlResult = await run(url);\n urlResult = urlResult.filter(filterResult);\n urlResult.forEach(result => console.log(result));\n }\n catch (e) {\n console.log('Error:', e);\n process.exit(1);\n }\n}\nWe also had issues with unhandled rejections sometimes caused by a session disconnecting or similar errors. To avoid Jenkins indicating our site was passing with 100% accessibility, when in reality it had not executed any tests, we instructed Jenkins to fail the job when an unhandled rejection or uncaught exception occurred:\nprocess.on('unhandledRejection', (reason, p) => {\n console.log('Unhandled Rejection at:', p, 'reason:', reason);\n process.exit(1);\n});\nprocess.on('uncaughtException', (err) => {\n console.log('Caught exception: ${err}n');\n process.exit(1);\n});\nNow it\u2019s your turn\nThat\u2019s it! That\u2019s how we automated accessibility testing for Elsevier ecommerce pages, allowing us to improve our site and make it more accessible for everyone. I hope our experience can help you automate accessibility tests on your own site, and bring the web a step closer to being accessible to all.", "year": "2017", "author": "Seren Davies", "author_slug": "serendavies", "published": "2017-12-07T00:00:00+00:00", "url": "https://24ways.org/2017/automating-your-accessibility-tests/", "topic": "code"}
{"rowid": 295, "title": "Internet of Stranger Things", "contents": "This year I\u2019ve been running a workshop about using JavaScript and Node.js to work with all different kinds of electronics on the Raspberry Pi. So especially for 24 ways I\u2019m going to show you how I made a very special Raspberry Pi based internet connected project! And nothing says Christmas quite like a set of fairy lights connected to another dimension1.\nWhat you\u2019ll see\nYou can rig up the fairy lights in your home, with the scrawly letters written under each one. The people from the other side (i.e. the internet) will be able to write messages to you from their browser in real time. In fact why not try it now; check this web page. When you click the lights in your browser, my lights (and yours) will turn on and off in real life! (There may be a queue if there are lots of people accessing it, hit the \u201cSend a message\u201d button and wait your turn.)\n\n\n\n\nIt\u2019s all done with JavaScript, using Node.js running on both the Raspberry Pi and on the server. I\u2019m using WebSockets to communicate in real time between the browser, server and Raspberry Pi.\nWhat you\u2019ll need\n\nRaspberry Pi any of the following models: Zero (will need straight male header pins soldered2 and Micro USB OTG adaptor), A+, B+, 2, or 3\nMicro SD card at least 4Gb Class 10 speed3\nMicro USB power supply at least 2A\nUSB Wifi dongle (unless you have a Pi 3 - that has wifi built in). \nAddressable fairy lights\nLogic level shifter (with pins soldered unless you want to do it!)\nBreadboard\nJumper wires (3x male to male and 4x female to male)\n\nOptional but recommended\n\nBase board to hold the Pi and Breadboard (often comes with a breadboard!)\n\nFind links for where to buy all of these items that goes along with this tutorial. The total price should be around $1004.\nSetting up the Raspberry Pi\nYou\u2019ll need to install the SD card for the Raspberry Pi. You\u2019ll find a link to download a disk image on the support document, ready-made with the Raspbian version of Linux, along with Node.js and all the files you need. Download it and write it to the SD card using the fantastic free software Etcher5. \nNext up you have to configure the wifi details on the SD card. If you plug the card into your computer you should see a drive called BOOT. There\u2019s a text file on there called wpa_supplicant.conf. Open it up in your favourite text editor and replace mywifi and mypassword with your wifi details6.\nnetwork={\n ssid=\"mywifi\"\n psk=\"mypassword\"\n}\nSave the file, eject the card from your computer and plug it into the Raspberry Pi. \nIf you have a base board or holder for the Raspberry Pi, attach it now. Then connect the wifi USB dongle7 and power supply, but don\u2019t plug it in yet!\nWiring!\nTime to wire everything up! \nFirst of all, push the Logic Level Converter into the middle of the breadboard:\n\nLogic Level Converter\nThe logic level converter may be labelled differently from the one in the diagram but the pins are usually exactly the same internally. I would just make sure the pins marked HV (High Voltage) are on the bottom and LV (Low Voltage) are on the top. \n\nRaspberry Pi pins only output 3.3v but the lights need 5v. That\u2019s why we need the logic level converter in there to boost up the signal.\nConnect the first two wires between the Raspberry Pi pins and the breadboard:\n\nNote that the pins on the Raspberry Pi are male, so you need a female to male jumper wire to connect between them and the breadboard. The colours don\u2019t have to match but it\u2019s easier to follow (and check) if you use the same ones as in the diagram. \n\nThen the next two:\n\nThis is what you should have so far:\n\nLights\nNow to connect the lights! My ones have a connector with three holes in it that I can push jumper wires into, and hopefully yours will too! So I used the male-to-male jumper wires to connect them to the breadboard.\n\n\n\nMake sure that you connect the right end of the lights, mine has a male connector at the wrong end so it\u2019s impossible to do this, but double check. \nAlso make sure that the holes in the light connector are the same as mine. To do this, follow the wires from the connector to the first light and look at the circuit board inside. You should just about be able to make out the connections labelled + (sometimes 5V, V+ or VCC), GND (or \u2018-\u2019 or G) and DI (sometimes DIN for data in).\n\nYou can just about make out the +, DI and GND on this picture. Note that on the other side of the board there is a DO for data out - that\u2019s what takes the data along to the chip in the next light. Make sure that you\u2019re plugging into the data-in and not the data-out! \nThat\u2019s it! Everything\u2019s plugged in and ready to go! But before you plug power into your Pi, double check all your wires and make sure they\u2019re exactly right! You could damage your Raspberry Pi if it is not wired correctly. So triple check!\n\nThe Moment of Truth!\nPlug in the Raspberry Pi and wait around a minute or two for it to boot up. If all is well, the lights should strobe rainbow colours for one second - that\u2019s your confirmation that it\u2019s connected to my WebSocket server and ready to receive messages from the upside-down! \n\nHowever, if the first light in the string is pulsing red, it means that you\u2019re not connected to the internet. So check the Troubleshooting section of the support document. If it\u2019s pulsing green then you\u2019re connected to the internet but can\u2019t connect to my server. It must have gone down. Sorry! The code will keep trying so leave it running and maybe it\u2019ll come back up. \nRig up the lights!\nFix the lights up on the wall however you want, pins, nails, tape. I\u2019ve used cable clips. Just be careful! I\u2019m using a 50 light string so I\u2019ve programmed it to use the lights at the end for the letters. That way I have just under half the string to extend down to the floor where I can keep the Raspberry Pi. \nCheck the photo here to see how the lights line up, note that there are spare unused lights in-between each row:\n\nNow visit lights.seb.ly and you\u2019ll see this : \n\nIf you\u2019re the only one online you\u2019ll have direct connection to the lights and any letter you click on will light up both in the browser and in real life. If there are other people there, you\u2019ll need to click the button to join the queue and wait your turn. \nHow it works - the geeky details!\nElectronics:\nThe pins on the Raspberry Pi are known as GPIO pins, general-purpose input/output. You can connect a wide variety of electronic components to them, LED lights, buttons, switches, and sensors. You can turn the power to the pins on and off using Node.js (or Python, if you prefer). \nAddressable LEDs or \u201cNeopixels\u201d\nWe\u2019re only using one GPIO pin on the Raspberry Pi (the other connections are 5V, 3.3V and ground) and that single pin is controlling all of the lights in the string. The code turns the pin on and off really fast in strictly timed morse-code-like dots and dashes to transmit binary data. The chips attached to each LED decode the binary and adjust the output to the LED accordingly. That chip then sends the data on to the next light in the string. \nThe chips on each light are the WS2811, part of the WS281x family that come in a multitude of different form factors and are often packaged with tiny LEDs in a single component. They are commonly referred to as Neopixels8 and I used them on my Laser Light Synths project.\nNeopixels with the chip and the LED all in one - it\u2019s the white square shaped component and the darker square inside is the chip. These are only 5mm wide!\nA Laser Light Synth! Covered with around 800 super bright neopixels!\nLogic Level Converter\nThe logic level converter is a really cheap and easy way to change the level from 3.3v to 5v and back again. You must be careful that you do not connect 5v into a GPIO pin or you will most likely damage the Raspberry Pi processor chip. \nPower\nNeopixels can often draw a lot of current so you need to be careful how you power them. I\u2019ve measured the current draw from the string to be less than 800mA so you should be fine wired directly to the 5V output. But if you use more lights or have them all on really bright at once, you\u2019ll need to use a separate 5V power supply. If you want to learn more, check out Adafruit\u2019s Neopixel Uberguide. \nNode.js\nThere are two Node.js apps running here, one on the Raspberry Pi and one on my server. You can see the code on my GitHub at github.com/sebleedelisle/stranger-lights for the Raspberry Pi and github.com/sebleedelisle/stranger-lights-server for the server. And they\u2019re hosted on npm as stranger-lights and stranger-lights-server. \nThe server side code sets up a standard web server to deliver the HTML for the web interface. It also sets up a WebSocket server that allows for real-time communication between the browser and the server. This server code also manages the queue and who is in control of the lights at any given time.\nWebSockets\nI\u2019m using the excellent Socket.io library to manage the WebSocket connection. Both the browser and the Raspberry Pi Node.js app connects to my WebSocket server. \nWhen you click on a letter in the browser, a message is sent to the server, which forwards it to the connected Raspberry Pi clients and also all the web browsers9. \nThe Raspberry Pi code\nThe Node.js app runs automatically on startup, and I made this happen by adding this to the /etc/rc.local file: \nnode /home/pi/strangerthings/client.js > /dev/null &\nAnything in the rc.local file gets executed when the Pi boots up and this line of code runs the Node.js app and routes its output to nowhere (ie /dev/null). The & means that it runs it in the background and doesn\u2019t hold up the boot process. \nWorking with the Raspberry Pi headless\nYou might know that when a computer has no screen or keyboard, you would refer to it as \u201crunning headless\u201d. So just like most web servers, you need to configure it over the network with ssh10. If you\u2019re on a mac you can find your Pi on the network through the name raspberrypi.local11, otherwise you\u2019ll need to find its IP address. There\u2019s more on the guide to Remote Access instructions on the Raspberry Pi website. And if you\u2019re very new to the terminal, I highly recommend this great online Linux command line tutorial.\nImprovements\nThis is quite an early experiment and I\u2019m sure I\u2019ll discover lots of optimisations over the next few weeks, especially if the server gets a proper hammering today! But there are a few things you can do. Obviously I\u2019ve just rigged up my lights with Post-it notes. It\u2019d be a lot nicer to get a paint brush and try to recreate the Winona-in-a-manic-state text style. \nWhere next?\nFinding quality resources about Node.js for electronics on the Pi can be somewhat hit and miss, but this is getting better all the time. Alternatively I am thinking about running some online courses, please let me know if that\u2019s something you\u2019d be interested in, or sign up to my mailing list at st4i.com. \nThere are many many more resources for the Raspberry Pi with Python (gpiozero is a good place to start), so if that language works for you, you\u2019ll be spoilt for choice! \nAlso take a look at Arduino - it\u2019s an incredibly popular platform for electronics and the internet is literally bursting with resources. \nI hope you enjoyed this little foray into the world of JavaScript electronics on the Raspberry Pi! If you get this working at home please let me know! Tweet me at @seb_ly. \n\n\n\n\nNot a particularly original idea, but I don\u2019t think I\u2019ve seen anyone do it quite like this before, ie using WebSockets, and Node.js on a Raspberry Pi. Other examples: Internet of Stranger Things, Strangerlights.com, and loads of examples on Instructables\u00a0\u21a9\ufe0e\n\n\nVideo guide to soldering pins on to a Pi Zero and further soldering advice from Adafruit\u00a0\u21a9\ufe0e\n\n\nSlower cards will work but performance may suffer\u00a0\u21a9\ufe0e\n\n\nOr \u00a35,000 in UK money. Sorry, Brexit joke :)\u00a0\u21a9\ufe0e\n\n\nYou will need a card reader on your computer - most micro SD cards come with an adaptor that fits standard SD slots. \u00a0\u21a9\ufe0e\n\n\nSSID and password should be all that you need but you can see all the config options on this wpa supplicant guide\u00a0\u21a9\ufe0e\n\n\nRaspberry Pi Zero will require the OTG to USB adaptor to attach the wifi dongle\u00a0\u21a9\ufe0e\n\n\nThanks to Adafruit who invented the term neopixels so we don\u2019t have to refer to them as WS281x any more!\u00a0\u21a9\ufe0e\n\n\nSo you can see other people sending messages in the browser\u00a0\u21a9\ufe0e\n\n\nssh is short for Secure Shell and is a way to connect to a remote computer and type in it just like you would in the terminal.\u00a0\u21a9\ufe0e\n\n\nYou can change this default hostname using raspi-config\u00a0\u21a9\ufe0e", "year": "2016", "author": "Seb Lee-Delisle", "author_slug": "sebleedelisle", "published": "2016-12-01T00:00:00+00:00", "url": "https://24ways.org/2016/internet-of-stranger-things/", "topic": "code"}
{"rowid": 221, "title": "\u201cProbably, Maybe, No\u201d: The State of HTML5 Audio", "contents": "With the hype around HTML5 and CSS3 exceeding levels not seen since 2005\u2019s Ajax era, it\u2019s worth noting that the excitement comes with good reason: the two specifications render many years of feature hacks redundant by replacing them with native features. For fun, consider how many CSS2-based rounded corners hacks you\u2019ve probably glossed over, looking for a magic solution. These days, with CSS3, the magic is border-radius (and perhaps some vendor prefixes) followed by a coffee break.\n\nCSS3\u2019s border-radius, box-shadow, text-shadow and gradients, and HTML5\u2019s - \n\t
![\"About](\"/img/slideshow/3.jpg\" "\\"\\"")
\n\nBy default, and without JavaScript, the third image in this slideshow is shown. When the JavaScript is applied to the page the slideshow must know to start from the correct place, this is why the start class is required.\n\nYou could capture the default image name and parse it to get the position, but only the default image needs to be numeric to work with this plugin (and could easily be changed in future). Therefore, this extra specifically defined option means the plugin is more tolerant.\n\nPrevious/Next Links\n\nA common feature of slideshows is previous and next links enabling the user to manually progress the images. The Cycle plugin supports this functionality, but you must generate the markup yourself. Most people add these directly in the HTML but normally only support their behaviour when JavaScript is enabled. This goes against progressive enhancement. To keep with the best practice progress enhancement method the previous/next links should be generated with JavaScript.\n\nThe follow snippet checks whether the slideshow requires the previous/next links, via the arrows class. It restricts the Cycle plugin to the specific slideshow using the selector we created at the top of the plugin. This means multiple slideshows can run on one page without conflicting each other.\n\nThe code creates a - using the arrows array we defined at the top of the plugin. It also adds a class to the slideshow container, meaning you can style different combinations of options in your CSS.\n\n// create the arrows\nif ($$.is('.arrows') && list.length > 1) {\n\toptions.next = selector + '.next';\n\toptions.prev = selector + '.previous';\n\t$arrows = $('
- with anchors listed directly inside without the surrounding